GTA
All Springer/NP/PCP Air Gun Discussion General => Machine Shop Talk & AG Parts Machining => Topic started by: darkcharisma on July 19, 2018, 02:30:11 AM
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So, I was watching Matts video on youtube and saw a set of pellet swaging dies. oh my word i want a set for myself. the tittle of the video is "A Lesson in the Wind | Stories From Patagonia, pt.4" from AirarmshuntingSA
at 7:40 is where Matt's buddy starting making his own pellets.
I wonder if someone here can tackle the task in a week or so either with a manual milling maching or CNC.
I am willing to pay for the prototype and test it out myself. as long as it's reasonable. maybe we can mass produce it to the airgun forum members here. I know there are pellet swaging dies from Corbin that would cost at below $300, but that's not for Diabolo pellets, but rather bullets with hollow base.
any takers? if so please pm me and maybe we can workout something that benefits airgunners.
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Those dies from China are about $800 but then you'll need the arbor press and whatever else to go along with it.
I've had really decent luck casting 25 cal diablo style and 22 cal boat tails from molds that I bought from NOE. rsterne (Bob) design's some fantastic molds but not any for the 22 cal diablo yet.
(https://farm1.staticflickr.com/838/43136887071_58a86c96db_b.jpg)
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I read a post on that mold you were referring to from NOE. everyone said they were nose heavy and wasn't accurate. now, yours has a flat nose. how do they group at 100 yards? or 50?
I contacted the seller he called them HEN molds. he did say $800 not including shipping. we don't have solid accuracy data on that HEN mold yet anywhere so I'd rather not spend that much money, unless the HEN molds were doing sub moa at 50. the alternative is Corbin swaging die at $289 currently, but those pellets won't qualify for competition and I have a smooth twist barrel, not going to work. Since i don't hunt, i am not leaning for the Corbin yet. I can buy loads of JSB, but that's not the point. I want to be able to make my own. If only the HEN could be somewhere max $300, ideally $200!
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The pic of the mold I posted here is the new one, I've got the old nose heavy mold and it's basically a paper weight now but I'm going to bring it over to my brother and see what he can do with it, he's got total access to a mold shop that he helped a friend of ours put together. He even rebuilt a lot of the machinery for him, my brother was a wiz in the mold business and he really does know his stuff.
I think that if you're in need of match grade pellets swaging good pure lead would probably be the most accurate. Next time I get a chance to stop over to my brother's place I'll put a copy of that youtube video on disc and see what he thinks.
I was kinda wondering about them those boat tails if they'd even be legal for competition airgun shooting because they're extremely accurate but you have to make them yourself ;)
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Guys hold on for a week, .22 cal (head 5.52mm) 18.52 grain 5 cavity mould is under development. Its for my own use I have a local machine shop assisting me to make it. 0.01mm tolerance is difficult to maintain on a manual milling center so they are using a Japanese 3 axis CNC for it.
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wanye, you forgot to mention about the accuracy of the new pellets. i am sure the boattails wont qualify for competition. at least for AOA extreme bench resst, they want diabolo pellets with skirts only. Utah challenge, i saw tethered lines...! so maybe their rules are different. IMO, you cannnot do anything to the old mold, since the head of the pellet is up, not down like traditional bullet molds. i was going to suggest putting pins in for hollow point. you may want to try making a plate for it on top and swage down the heads for hollow point right after casting and cuting the sprue plate. i dont know how the mold will hold. i am sure it will be fine since little force is needed. try that Wayne! and tell me about the accuracy please.
Ken! i am going to hold you to the “week” timeline. please get in touch with me/us as soon as you have the mold perfected! i do shoot .22 but id rather have lots of .25. why dont you push them to make .25 in the 35grains while your at it? anyhow please report back!
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Sure, .25 is possible. Just let me know how long you want it to be, to fit the mag. accordingly I can work on the design and FEA,CFD analysis of the pellet (that's how a JSB is designed and made, Rigorous computer assisted analysis and simulations)
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Ken, you can either copy the dimensions from the JSB .25 34 grains. or use Bob's pellet design for Hatsan magazines. the length is .420, see the attachment below. credit goes to BOB. The only thing i would modify on his design is making it DOMED instead of flat head, I like it domed. and I want the hollow base depth at 0.050, not 0.150! that way we can use 3 different hollow punchers to work it's weight accordingly. Its good to have you work on this KEN! you have no idea how hopeful i am right now!
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These are the specs. and the pics
the domed design with .250 as its radius doesnt fit in under length .420, its goes beyond it. so i made the changes that are proportional to the drawing
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dude, that's quick. looking at the first picture. it doesn't show any turbulence airflow behind the head, does that mean it's going to be stable in flight? or is this simulation only and needed real world testing to compare? what are your thoughts?
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Yes the area behind the head has zero pressure and there is little or no air acting on that area, I have been doing a research analysis using CFD on same subject for Fluid flow. The airflow shows a symmetric vorticity in the wake at the tail, it means that nothing is abnormal with high drag design (which looks like a parachute), yet the pellet shoots like shotgun? why... many reasons some being the inconsistent casting and deformed heads which deflect the pellet due to spin and inertia. the domed one looks promising (with slight changes to skirt it will be perfect).
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the skirt needs more mating surfaces. like the ones shown here, instead of relying on the ends of the skirt to squeeze and mate with the barrel for stability. if i can, i'd rather get rid of the skirts and have a bullet design with two sections of small mating surfaces, one behind the head, and one at the tail to reduce drag in the barrel but still keep it tight to the bore from breech to muzzle end until it gets choked down. But that's just me.
bullet balance and weight designed for the twist rate is a good start for accuracy. bullet tolerance and aerodynamic is the second. airflow and muzzle blast would be third when the bullet exits the barrel. ah...i don't want to think about it. there's probably more to it than that lol.
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Those dies from China are about $800 but then you'll need the arbor press and whatever else to go along with it.
I've had really decent luck casting 25 cal diablo style and 22 cal boat tails from molds that I bought from NOE. rsterne (Bob) design's some fantastic molds but not any for the 22 cal diablo yet.
(https://farm1.staticflickr.com/838/43136887071_58a86c96db_b.jpg)
WAYNE, I am still waiting for you to chime in on the accuracy of the molds you showed. any infor would be appreciated.
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everyone said they were nose heavy and wasn't accurate.
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I have a smooth twist barrel
With a smooth twist barrel and its low effective spin rate; you want "nose heavy" and a conventional "waisted" shape, optimized for drag stabilization.
The revised "Monster" ultra heavy JSB pellets have very short waists and long conical skirts. They are much more accurate than the ones with the long cylindrical "fat" waists. Especially from FX ST barrels.
Wayne's cast pellets (Bob's) look like JSB pellets known to produce good accuracy from FX ST barrels.
The shape of pellet you presented (below) may work with conventional rifling, but will not work very well with smooth twist barrels:
(https://www.gatewaytoairguns.org/GTA/index.php?action=dlattach;topic=145968.0;attach=234963;image)
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everyone said they were nose heavy and wasn't accurate.
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I have a smooth twist barrel
With a smooth twist barrel and its low effective spin rate; you want "nose heavy" and a conventional "waisted" shape, optimized for drag stabilization.
The revised "Monster" ultra heavy JSB pellets have very short waists and long conical skirts. They are much more accurate that the ones with the long cylindrical "fat" waists. Especially from FX ST barrels.
Wayne's cast pellets (Bob's) look like JSB pellets known to produce good accuracy from FX ST barrels.
The shape of pellet you presented (below) may work with conventional rifling, but will not work very well with smooth twist barrels:
(https://www.gatewaytoairguns.org/GTA/index.php?action=dlattach;topic=145968.0;attach=234963;image)
Thats true.
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i agree. it will be semi okay at shorter ranges up to 25 yards probably even with smooth twist. but its a compromise unless we get a custom unchocked barrel. thats going further than the intended purpose here. these slug types of bullets sized for .223 will be perfect for my condor .223 barrel though. but thats easily done with casting. onto the topic at hand. Ken, your progress is eagerly awaited
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Punches are ready, Mould will be ready in next 2 days.
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That looks awesome from here dude! Nicely grounded and polished. needs to be mirror polished though. the nicer looking the better! keep it up dude. post a video review of the pellet accuracy here or pm as soon as you can!
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Guys hold on for a week, .22 cal (head 5.52mm) 18.52 grain 5 cavity mould is under development. Its for my own use I have a local machine shop assisting me to make it. 0.01mm tolerance is difficult to maintain on a manual milling center so they are using a Japanese 3 axis CNC for it.
I ran into the incredibly precise tolerance when making my own pellet head sizer with my small benchtop lathe and a small milling machine. With my lathe I couldn't bore a hole within a couple .01mm using a small boring bar so I started with a piece of O1 tool steel and drilled a 4 mm hole in the center. Then I reamed the 4mm hole with a home made piloted "D' reamer that created a stepped ream with an undersized "sizing ring like this sketch........
(https://i.imgur.com/p2Nqal1l.jpg)
The sizing ring in the die was then lapped till a pellet head pushed through the sizing ring had the size I wanted (rather long/tedious process). Here is the result showing a few versions of the sizer and various "D" reamer designs I tried ...........
(https://i.imgur.com/W3VEuBHl.jpg)(https://i.imgur.com/aIhAApFl.jpg)(https://i.imgur.com/qq9O7bDl.jpg)(https://i.imgur.com/2OvrYHql.jpg)
To use I first drop an unsized CPL into the die................
(https://i.imgur.com/K4d1uSdl.jpg)
The "ram" is inserted in the die............
(https://i.imgur.com/1E9ZvKCl.jpg)
Then I insert the "ram" to push the pellet head through the sizing ring and expand the pellet skirt while making it perfectly round. The ram is at a fixed position in the holder so only the pellet head gets sized..........
(https://i.imgur.com/mm8jrFcl.jpg)
Then the sized head is pushed back out of the die.................
(https://i.imgur.com/JUd22a9l.jpg)(https://i.imgur.com/nzvhfcBl.jpg)
The sizing of each pellet takes about 5 seconds while watching YouTube airgun, machining, whatever videos..........
(https://i.imgur.com/aIhAApFl.jpg)
Here are some 1250 count boxes of CPLs that were headsized watching videos and later sorted by weight...........
(https://i.imgur.com/bG6zjG8l.jpg)
The reason I'm mentioning my CPL pellet head sizing process is simply because I found it extremely difficult to get a pellet head of a specific size till I added a "sizing ring" to the die that could be lapped to the proper size. I'm wondering if a person could make a "5 pellet mold" (mould indicates casting to me) with consistent pellet heads with a 0.01mm tolerance, even with the larger .22 cal. I'm thinking that a .22 cal swaging die might give 0.01mm accuracy, however that would indicate a single die with a complicated high pressure press.
Anywhoo.........even the "big pellet swagers" (like JSB & H&N) have issues maintaining a consistent .177 pellet head and this JSB Exact pellet sort shows a .10mm variation with most varying about .04mm straight from the tins.........
(https://i.imgur.com/5vGMBDxl.jpg)(https://i.imgur.com/udeSRarl.jpg)
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Thanks for sharing an excellent point about how precise these molds needed to be. IMO, i think that may be another needed step once the pellets are swaged. If in case the pellet swaging molds do not provide a consistent headsized to pellet specifications. It's actually ideal to have a head sizer, that way we have some control over the finished pellet. it's also not bad for 5 secs per pellet to be sized. ha, I haven't thought about that at all...that's brilliant, mate!
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Thanks for sharing an excellent point about how precise these molds needed to be. IMO, i think that may be another needed step once the pellets are swaged. If in case the pellet swaging molds do not provide a consistent headsized to pellet specifications. It's actually ideal to have a head sizer, that way we have some control over the finished pellet. it's also not bad for 5 secs per pellet to be sized. ha, I haven't thought about that at all...that's brilliant, mate!
I've found that as long as the pellet head is large enough to be "swaged a bit" when loading into the leade all pellets will be the same size when loaded and shot. The problems I had were when some "pellets from the tin" had undersized heads and they were "loose in the leade" giving a flier. I tried sizing the supposedly 4.52mm JSB Exacts using my 4.50mm die and it was pretty much a useless endeavor since so many pellets from the tin had undersized heads to begin with.
I've always had good accuracy with the boxed CPLs, even when unsized, because their heads are usually 4.53mm-4.55mm (I do get about a half dozen odd-balls in a 1250 count box). Pellets taken from a Die B box of CPLs at random...............
(https://i.imgur.com/qbrnYqjl.jpg)
The large head sizes makes for a rather tight fit in the leade but that only served to guarantee that each pellet was the exact same size when it was traveling down the bore and exiting the choke at the muzzle. I never had issues when shooting unsized CPL from my .177 R9, however my newer .177 HW95 has a tighter leade which made loading CPLs a "sore pellet pushing finger affair" after a 100 shot shooting session. Shooting CPLs from the HW95 was the reason I started sizing CPLs in the first place. I found that sizing my CPL pellet heads to 4.50mm created a pellet that was accurate from either my looser leade R9 or tighter leade HW95 without the "sore pellet pushing finger affair"! I later bought a spare HW95 barrel from a Canadian company when they were closing out their inventory of HW parts and when it arrived I noticed that it also had a tighter leade just like the barrel that came with the HW95. It could have just been coincidence but perhaps HW has tightened up their .177 leades a tad.
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Well the 0.01 mm tolerance is with reference to plunge rate of a CNC and tool sizes. If I overcut or undercut the cavities then chances are that it will produce slightly oval pellets. the end results of a cast or swaged pellet will vary. What I mean to say is that a manual machine cannot guarantee me the 0.01 mm precision, while a cnc does (while making the mould). I anticipate a max deviation of 0.1 mm in pellet size, and min of 0.05, Lets hope its less. Large scale manufacturers have forming rate in excess of 50 pellets a minute while I am anticipating 5 pellets per 2 minutes of forming using hand held mould and die, hence the time based
variables get reduced, but the machined part will create its own variation based on use over time. I am using a 0.2mm ball cutter and a cnc mill (Dark charisma this is the tool that breaks too often). So lets hope for the best.
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Ken,
It sounds like you need to spin your two mold halves, while they are clamped together, around the pellet's long axis, to finish cut the cavity. This will ensure that the cavity is round and even.
The bulk of the material can be removed from each mold half, one at a time before clamping them together.
Best performed on a 4-axis mill with a rotary table, so that the axis of rotation depends on a set of true running roller bearings, rather than the digital capability of the mill, at such a small scale.
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Ken,
I am surprised that you need to go to a .2 mm diameter ball cutter. What is the smallest caliber pellet you are trying to make with this?
I would have thought that you could interpret a .22 or larger caliber pellet design, such that it would be functionally equivalent when made using a .5 or even 1 mm diameter ball cutter.
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Guys hold on for a week, .22 cal (head 5.52mm) 18.52 grain 5 cavity mould is under development. Its for my own use I have a local machine shop assisting me to make it. 0.01mm tolerance is difficult to maintain on a manual milling center so they are using a Japanese 3 axis CNC for it.
I ran into the incredibly precise tolerance when making my own pellet head sizer with my small benchtop lathe and a small milling machine. With my lathe I couldn't bore a hole within a couple .01mm using a small boring bar so I started with a piece of O1 tool steel and drilled a 4 mm hole in the center. Then I reamed the 4mm hole with a home made piloted "D' reamer that created a stepped ream with an undersized "sizing ring like this sketch........
(https://i.imgur.com/p2Nqal1l.jpg)
The sizing ring in the die was then lapped till a pellet head pushed through the sizing ring had the size I wanted (rather long/tedious process). Here is the result showing a few versions of the sizer and various "D" reamer designs I tried ...........
(https://i.imgur.com/W3VEuBHl.jpg)(https://i.imgur.com/aIhAApFl.jpg)(https://i.imgur.com/qq9O7bDl.jpg)(https://i.imgur.com/2OvrYHql.jpg)
To use I first drop an unsized CPL into the die................
(https://i.imgur.com/K4d1uSdl.jpg)
The "ram" is inserted in the die............
(https://i.imgur.com/1E9ZvKCl.jpg)
Then I insert the "ram" to push the pellet head through the sizing ring and expand the pellet skirt while making it perfectly round. The ram is at a fixed position in the holder so only the pellet head gets sized..........
(https://i.imgur.com/mm8jrFcl.jpg)
Then the sized head is pushed back out of the die.................
(https://i.imgur.com/JUd22a9l.jpg)(https://i.imgur.com/nzvhfcBl.jpg)
The sizing of each pellet takes about 5 seconds while watching YouTube airgun, machining, whatever videos..........
(https://i.imgur.com/aIhAApFl.jpg)
Here are some 1250 count boxes of CPLs that were headsized watching videos and later sorted by weight...........
(https://i.imgur.com/bG6zjG8l.jpg)
The reason I'm mentioning my CPL pellet head sizing process is simply because I found it extremely difficult to get a pellet head of a specific size till I added a "sizing ring" to the die that could be lapped to the proper size. I'm wondering if a person could make a "5 pellet mold" (mould indicates casting to me) with consistent pellet heads with a 0.01mm tolerance, even with the larger .22 cal. I'm thinking that a .22 cal swaging die might give 0.01mm accuracy, however that would indicate a single die with a complicated high pressure press.
Anywhoo.........even the "big pellet swagers" (like JSB & H&N) have issues maintaining a consistent .177 pellet head and this JSB Exact pellet sort shows a .10mm variation with most varying about .04mm straight from the tins.........
(https://i.imgur.com/5vGMBDxl.jpg)(https://i.imgur.com/udeSRarl.jpg)
I will definitely look forward to it. You are right about the pellet size variation. Precision reaming,Boring and Grinding operations take time and produce one of a kind job. Your pellet sizing project is a amazing.
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Ken,
I am surprised that you need to go to a .2 mm diameter ball cutter. What is the smallest caliber pellet you are trying to make with this?
I would have thought that you could interpret a .22 or larger caliber pellet design, such that it would be functionally equivalent when made using a .5 or even 1 mm diameter ball cutter.
Yeah the smallest caliber of .177 can be machined, Majority of rough cuts are taken care by a 0.5mm ball cutter, while a 0.2mm cutter is used for finishing touches. As of now I am making one for myself, so I am experimenting with the machining capability.
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Ken,
Do you have access to an EDM machine? If I wanted to make dies for pellets, I would start with pre-hardened steel. Then use an EDM to burn the pellet cavity; while rotating the copper electrode.
This would require that the die half be advanced towards the mid-line. It may be easier to burn one cavity, then the other; although finishing should be done by burning them closed together, aligned by their permanent alignment pins.
PS: Did you see my edit posted here: https://www.gatewaytoairguns.org/GTA/index.php?topic=145968.msg1486375#msg1486375 (https://www.gatewaytoairguns.org/GTA/index.php?topic=145968.msg1486375#msg1486375)
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I have accress to EDM machines locally where I live. But they say it will be very expensive....EXPENSIVE is not something we are aiming for unless there is a big demand/market for these pellets/mold being produced. for prototyping which is pellet accuracy dependent, lower means of production is approached first. EDM is a different animal and i have no idea how the profiles of a diabolo pellet or skirts or bullet profiling in general gets cut. i am sure we can use o1 or a2 alloy to mill in annealed state and harden it later. these steels are non shrinking, even so we can take care of the tolerances of the cavities with polishing or other means. i can make one cavity all day long with crude manual lathe and mill, but thats not the point. we want consistency of pellets from accross 5-10 cavity molds.
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duy,
Whatever machining method you use; A2 steel is a good choice because it does not require quenching in oil (or water); thus distortion on cooling is minimized. O1 may not shrink after quenching, but it may still distort too much.
The pre-polished dimensions of commercial pellet dies are almost certainly cut with EDM. Anyway, Ken reminded me via PM that EDM requires process development to cut a given cavity shape and size to the desired critical dimensions. Ken does not have the time for that, and machining is more predictable; so that is what he is doing.
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I looked into which type of material would be best for die and molds. between s7, a2, o1, h13 and p20, even 420. A2 is best as far a availability and price for it's excellent heat treat ability and tooling life. o1 comes close behind if both machined in it's annealed state. If we use A2 bars in the thickness of 3/8 minimum, we still have alot of meat on the sides making .25 pellets. I dare say .30 or .308 pellets can be used without much compromise on structure integrity. I am not too worried about distortion, we can ream with the cutter once again.
I have no comments on EDM. I know nothing of it accept its very precise. I think it's best to aim for simple methods first until we really needed to go all out.
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I am not too worried about distortion, we can ream with the cutter once again.
Yes; but only if you plan to leave a finishing allowance. If you machine to the nearest 0.01", and then have distortion after hardening, your cavities will be oversized after you clean them up.
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you know, your right about finishing allowance. I am sure after heat treating and tempering, cleaning up needs to be done with oil residuals and who knows what else is deposited on the top layers. So, undersized cavities milling, heat treat, tempering, and ream. sounds like a good plan but probably not needed once we push production with prehardened steels. we are just prototyping for precision milling right now and i was suggesting milling annealed steels to save tooling cost. if for every 10 molds made, 3 sets of end mills lost. that's almost like loosing 1 mold worth in cost.
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If you make swaging dies from annealed steel without hardening, you best keep the walls thick, or the dies will bulge when you use them. To swage a fully formed pellet with such fine details can take 20,000 to 50,000 PSI pressure applied to the lead.
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I was wondering about the compression psi myself. 20k-50k is a large gap estimate. anyway we can verify the numbers? i have seen Chinese people hammer it down by light tapping it. besides, the lead bleeds on top of the punch, not compressing without relieving pressure by means of bleeding. I am not sure if it takes high psi to do it at all.
. no, we have every intention to harden the steel, it's a matter of before or after the milling. to mill with Ken's set up is to loose end mills with harden steels every 3-4 molds. to mill it annealed will be estimated 1 set of end mill every 10 molds. end mills are not cheap.
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Tapping a small diameter punch with a hammer produces very high instantaneous, but unknown force. Thus, high but unknown pressure.
Squeezing with an arbor or hydraulic press will enable you to judge how much pressure you need to fully form your pellets. If you have bleed holes, lead should flow to prevent over pressure, and the punch should travel until it stops on its shoulder.
You can form basic cylinder shapes in lead at less than 5,000 PSI. Forming a waisted pellet with a hollow base will take more pressure. Your bleed holes need to be small or you won't reach this pressure...
When I first joined this forum, I was trying to swage slugs for Matt Dubber with some very basic dies I made. The image below shows the very first two styles of projectiles I swaged. After that, I experimented with driving bands and hollow bases. Those projectiles took an estimated 50k+ PSI to fully form, based on the .22 punch area, and the 1500 LB ram force I was applying. Such pressure was yielding the thin sections of my dies, until I hardened them; or cut them from hardened steel.
(https://www.gatewaytoairguns.org/GTA/index.php?action=dlattach;topic=125617.0;attach=186290;image)
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the more i look at the bullet type pellets...the more i want to do it. I got a Huben K1 in .25, i probably need bullets. how did it turn out for Matt and those bullets? you are probably right about swaging bullets with bleed holes and deep hollow bases. Corbin has dies threaded for reloading press use. same or double force is applied with those press probably. what material did you use for the mold and cutter?
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The mould is ready. Its still not up to mark. The dimensions are perfect but while machining the second half got offset by 0.01 mm, Maybe due to probe or metal burr. The two parts are flush with little or no parting gap, but the offset wont create a perfectly round pellet. a small step might get created while doing so. I am going in for machining the second side, with corrections and better truing techniques. I couldn't cast or form the pellets today. I will do it in next few days.
Things need to be rectified and modified, lot to learn from first attempt.. ...... Yes the machining is accurate, but with better truing it will be perfect. Time for "Round 2"
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Not bad for first attempt Ken. i can see one cavity offset and the undesirable finish. can you post some pictures of the cutters? what type of steel were those cutters? we definitely need to undersize the cutters to compensate for offsets and such then ream it out (optional operation even with tempered steel).
surface harden can be done with nitriding and coatings but thats not our objective here with 316. try punch swage or melt and swage a couple of pellets and post it here. no need to cast
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I cannot post sensitive info about the cutters, There are few trade secrets that need to be kept like KFC and Coke (LOL). All the profiles are distorted in same way. Tell me guys, should I proceed with machining the other side of 316 steel, or start fresh with something harder like tool steel?
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Its understandable Ken. But for machinists, we kind of already know and have our own methods visualized in our heads. its a matter of which methods we haven’t explored for the most efficiency, and desirable product.
move on to carbon or alloy steels. certainly can eliminate some mistakes while provide better surface
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Ken,
I suggest you make another second "mold" side from the same material the one with the offset. Finish what you started.
If I was machining these die halves "one at a time", I would create a toolpath that actually cuts the both in one set up; as if it were one long piece. By cutting a little in one pocket before moving one, tool wear can be distributed, rather than accumulated towards the last cavity; and the second die-half.
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Duy,
I started with O1 tool steel. Also used A2. These were cut annealed with a carbide burr, already close to the nose profile I was looking for (after removing the bulk of the material with a carbide endmill).
(https://images1.mcmaster.com/mvB/contents/gfx/large/43035a68p1l.png?ver=1268047663) I used up a few of these: https://www.mcmaster.com/#43035A227 (https://www.mcmaster.com/#43035A227)
After all that, I would recommend A2. Heated bright hot, after applying a thin coating of scale preventative coating; and quenched in a cold air stream.
Made a few die bodies from prehard 4140.
Base punches were made from commercial pre-hard HSS blanks. When shaped to produce hollow bases, the HSS was cut with diamond coated burrs.
I also made cut a few nose cavities into gauge pins (62 Rc). I used diamond coated burrs to cut the gauge pins. The burrs were driven by a die grinder, mounted in a fixture in the mill vice. The gauge pin was in a collet in the mill spindle. I covered the mill such that dust from the gauge pin and from the diamond burr could not fall onto the mill slides, and used a vacuum to clean up the bulk of the dust...
Anyway, it turns out FX smooth twist-X barrels work best with .217" diameter slugs. Matt had asked me to make my experimental slugs "tight", without giving me actual diameters. I had asked for exact values, but in retrospect, think that Matt's NDA with FX precluded him from sharing that with me; or they simply would not give him that info. Considering what I was trying to do, I should have politely declined to proceed without exact info...
Anyway; I found Walther-Lothar air rifle barrels diameters listed, so I made the pellets in .22, .221 and .2215". Matt reported less than good accuracy with my slugs. I think this was due to projectile distortion, starting with the high loading force he experienced due to the slugs being "over sized".
At that time I found NSA slugs, and suggested Matt try some in .217" diameter. They worked very well, and became the slugs FX use to develop their smooth twist-X "slug barrel". The rest is history.
As had been producing the dies and slugs for free, I decided to spend my time on something else; rather than try to compete with NSA slugs.
If I had spent more time researching the use of slugs on GTA, before proceeding, I would have realized that when it comes to choked airgun barrels, tighter is not better. That the default starting point should be .217". Matt was on a tight schedule to go and visit the FX factory, where he wanted to test my slugs, so I was rushed into picking a few slug diameters and getting on with it. I told him what diameters I was going to make before I started, and he did not dissuade me with "how about a bit smaller"... Can't say it wasn't fun, despite the outcome.
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good deal Sub,
I was researching to see if Carbide Burrs can be used to cut the nose profiles for diabolo pellets.i did not find an oval burr on amazon, ebay or my favorite MSCdirect retail. i should have looked into Mcmaster. yet again, i arrived at the conclusion for the simplest method. that grounded cutters from .257 W1 should be used, but just undersize it by 25% and ream the two halves on a lathe into a predrilled .245 hole. this is by far the easiest method for the pellet profiles designed by Bob, biabolo head and skirt but flat body.i can make up to 5 cavities this way with a four jaw chuck. just advance to the next predetermined cavity by adjusting two chucks. i got o1 blanks for making axe heads in the thickness of 3/8. i can prototype it but i needed to wait for a .250 reamer to make the alignment holes. eh...i am not always prepared on the tooling aspect, this is why every project is halted to a crawling state...just waiting on tools...
LOL, something bugs me the same when people do not give precise specs or secretive about certain infomation related to the project at hand. i am sure it feels as if you had a few doors or rather manholes to crawl out of and you need to pick the right one or its failure...almost like a wackamole game except your the mole.
I know NSA has been out for a while, but for airgunners that wants to role their own pellets. you could have scored a piece of the pie. though i dont know how big the market is for pellet swaging. nonetheless, it is what it is, Matt wasn’t the deciding factor. he was just asking for directions...probably.
the slugs you made were really good looking. i am guessing half of the tail section was made to groove diameter and the head section was to the bore?
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i am guessing half of the tail section was made to groove diameter and the head section was to the bore?
That was the idea. Although Matt then asked for ones without any step, so that is what I shipped him. Achieved by sizing down after initial forming. See attachments:
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i see that you used a .22 LR profile and applied it to your bullet. i also read that flat base bullets perform poorly under speed of sound due to greater turbulence at the base. also, flat base bullets center of gravity is base heavy compared to boat tails. airgunners fall right into this section, we cant easily push the heavy base bullets supersonic to retain accuracy at shorter ranges. what i am saying is flatbase works best supersonic at short range. boat tails works best both over and under supersonic at long range while short range is average. thats why factory huben pellets works well. also due to the fact that they have a thin section at the base to seal the groove but not strip excess lead like the bullets you have.
do you want to try it again? make a boat tail and thinner groove section at the end? its proven with huben pellets but its nice to confirm all these theories we read so much about.
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Ken,
I suggest you make another second "mold" side from the same material the one with the offset. Finish what you started.
If I was machining these die halves "one at a time", I would create a toolpath that actually cuts the both in one set up; as if it were one long piece. By cutting a little in one pocket before moving one, tool wear can be distributed, rather than accumulated towards the last cavity; and the second die-half.
you mean to set th mold halves onto a self center vise with the cutter at midline while the halves advances towards mdline? that would be ideal isn’t it? the vise it self is expensive though.
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If I made more slugs, they would be in .25 cal...
Boat tails "work better", as in have reduced drag. Accuracy tends to be better with flat based projectiles.
The box in the image with "Huben" written on it contained these, effectively "rebated boat tail" projectiles. Made by AA for black powder revolvers; resized down from .2245 to .2215" by me. They were very hard lead. Matt now swages his own Huben style slugs from pure lead. One of my post on GTA link directly to that section of one of his recent videos:
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Dubber swages his own Huben slugs. Video starts at point of interests: https://www.youtube.com/watch?v=xXhg9J44mWk&feature=youtu.be&t=17m22s (https://www.youtube.com/watch?v=xXhg9J44mWk&feature=youtu.be&t=17m22s)
Close to the Huben bullets; without all the undercut little grooves: https://www.youtube.com/watch?v=i807-jyVF70&feature=youtu.be&t=4m36s (https://www.youtube.com/watch?v=i807-jyVF70&feature=youtu.be&t=4m36s)
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Sub, I really need to speed things up then. Got a Huben in .25 coming in next week, but I dont have any .25 slugs.
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you mean to set th mold halves onto a self center vise with the cutter at midline while the halves advances towards mdline? that would be ideal isn’t it? the vise it self is expensive though.
No. Unless I misunderstood, Ken is milling one set of die-half cavities to completion. Then setting up and milling the second die-half.
I was suggesting that both steel blanks be attached to the mill table in one long "train" (unless you have a really long vise). That the blanks be faced, and then rough and finished cut; as if it is on really long die half that happens to be split already. The idea is that all cavities are equally deep, and that tooling wear be distributed.
To distribute tooling wear, don't start at one and and finish on cavity before starting the next. Take them all to 10%, then 20% and so on. Cut the last 2% as a finishing operation, applied to all cavities. Thus the drift in size due to tool wear is minimized.
By making such a "train"; the tolling holes for both die-halves can also be cut in one set-up.
Huben slug videos found: https://www.gatewaytoairguns.org/GTA/index.php?topic=145968.msg1487104#msg1487104 (https://www.gatewaytoairguns.org/GTA/index.php?topic=145968.msg1487104#msg1487104)
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Ken probably meant turn the milled half down and mill the opposite half. so 5 cavities on each opposite end.
the "train" concept in plain words have not been visualized. are they clamped down along the longitudinal length, and each half apart and then mill each end like the illustration below? So, end mill in midline advances left and right lateral by .125 for 25 caliber each time (example)? this is looking down the Y axis, or looking down at the mill table.
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Having the opposing side meet like that is probably a good thing.
The train or sequential half-die idea I suggested could have them stand on the bottom, as your diagram shows.
It is a matter of knowing your mill. The train carriage die-half idea would require you to flip one of the blocks around. If there are mismatches caused by other factors, then holding the blocks the way you show will be more immune from them. Even if you don't simultaneously close the two die halves.
As for cutting, while simultaneously closing the die-halves towards the mid-line; that would "trap" the cutter and tend to cause chattering. Also, you would make sure that you have removed all the dust between blocks on your final cut. Ditto for any burrs on the cavity edge.
I think that rough cutting while the complimentary cavity halves facing each other, but spaced apart would be good. Then deburr the cavity edges, clean and clamp shut; before the finishing cuts are made "seamlessly". With the mold halves together, flushing the dust out with a strong air or fluid stream would be a very good thing. Else the cutter would be chasing the swarf around, potentially scratching the cavity.
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Boat tails are remarkable little airgun slugs for sure, I'm really liking the way my latest mold for 5 cavity .22's is working. They're pretty much a no brainer to cast as well and I love them in my SPAM16.
(https://farm1.staticflickr.com/930/41839099080_675cca9059_b.jpg)
A swaged slug of this design would undoubtedly perform better than the cast but for now I'm very content with the results that I'm getting from casting.
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The alignment is not an issue (that's what my machinist said now), we are re boring the dowel pin and increasing it to 6mm with both faces zeroed in and clamped. I hope that it makes the offset go away.
I got to know the root of the cause, It is important to use hardened tool steel. I am using SS, hence it requires surface grinding after every operation to retain a flat surface. I haven't started the work on Subs, and Dark Charisma's recommended material, First i want to verify the pellet dimensions and weight after swaging (just a matter of few hours from now). One the dimensions are true then I will immediately take up tool steel.
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we are re boring the dowel pin and increasing it to 6mm with both faces zeroed in and clamped.
Nice save!
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Wayne, that slug design would be easy to make. and swaging will be so much cleaner and faster than casting. you must cast for straight pellets to use in the swaging die, but after that it's precision swaging madness. I know you send me some accuracy data about the slug, I would like to see a better data if you can Wayne. at 50 yards using paper targets, measure the rings, put your pcp on a solid bench. I am already beginning to machine the cutters for the boattails. it's a matter of which weight I want for .25 and if i want to implement round nose or not.
Ken, give us an update as soon as you can, pictures are anticipated. oh yeah, tool steel all the way. even low carbon steels will work. just don't touch mild steel. anything in the 1045 and up is good, we can temper it down to around Rc40 hardness or so...
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Guys, one problem solved, other one just popped out. The 2 halves of the mould are aligned but the punch guide plate and top portion of plate is offset by 0.4 mm. I didn't have access to lead wire so I cast 3 pellets from the last .22 cal pellets I had. They came out frosted, but were perfect until I punched the rear cavities. The mould is perfect but the material is not ideal (S.S. 316). Since there are no vent lines, the pellets tend to stick to the walls until tapped out (that's where I damaged those else they are perfectly round). Parting lines are barely visible and may be wiped out with a cloth. I've placed an order for tool steel from Germany, It will arrive in few days. Some changes need to be made to the overall mould design.
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It's a good start Ken,
I thought the previous mold pictures had gaps between the cavities. did you torque the screws on the sides to minimize the gap? what about the pellet skirts on the first picture? i seems a bit thicker on one side. try pushing the pellet through a barrel. let see how it engages the lands and grooves. any caliper handy for skirt, head, and overall length measurement?
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Yeah, the skirt walls are thicker than expected. I will work on countersunk which may prevent the punch to plunge in. I don't have any measuring instruments right now. I will post about the measurements tomorrow as I am heading back to my machinist for "Round 3". :P ;D . A micrometer will be the perfect instrument to measure the dimensions.
The parting lines in yesterday's post were due to overlapping edges, Today the parting lines were visible but the mould fastening bolts were well torqued.
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Ken,
Those pellets look pretty good.
It looks like your base punch is near parallel in diameter. That means the pellet skirt thickness is thinnest some distance away from its rear lip. This would be unconventional. A tapering punch could be made for constant skirt wall thickness, or to taper; such that the thinnest portion is at the rear.
A tapering punch will pull out of the pellet easier, and create flow that will help fill out the cavity at lower axial force on the punch.
If it were mine, I would start with a punch that has the same taper as the outside of the pellet skirt; at a diameter that leaves the skirt wall on the heavy side. Perhaps 1 mm for a .22 cal.
The beauty is that you can make a few different base punches and try them.
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i dont think Ken has a “step” in the skirt taper like the ones here from China.
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Duy,
It looks as if that narrow band at the punch OD is intended to have excess lead bleed past the punch. Some of the videos of (similar?) Chinese dies being used show the flash being trimmed off by sliding a blade over the top of the two die-halves while they are still together.
Is this the plan; or how will excess lead be bled off?
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Like i said in a previous post before while we were discussing about psi. the lead will be bleeding off around the punching die, and gets cut off with a razor knife or something like that. simple and stupid is the motto here. well, more like...i dont wanna do anything else fancy to drive cost of production up haha.
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Bleeding around the punch works. Ease of use, and cost are the main factors, after pellet design quality and "production" consistency.
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Those are looking really nice for sure !!!
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Actually I use CAD to drive manufacturing decisions, My punch has a steps which are with reference to the balance of the pellet. The CG is adjusted through depth of the rear cavity. My design has CG at centroid of the pellet while being 18 grains and 7mm long.
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My design has CG at centroid of the pellet while being 18 grains and 7mm long.
Ken, I could not imagine anyone putting this much effort into making dies, unless they were designed in CAD.
The relationship between the CG and the centroid is important:
1. Diabolo pellets that work out of smooth bore barrels have their CG well forward of the centroid because they rely completely on drag stabilization.
2. Bullets usually have their CG behind their centroid and must be spun "fast enough" about their long axis to remain stable in flight.
There are an infinite range of possibilities between these two principles. I would suggests that FX smooth twist barrels operate closer to #1 than #2. Thus, your pellets may work better out of barrels that achieve faster spin rates, than FX smooth twist barrels. If that is the case, a different base punch design could be made that works with smooth twist; even if that requires reducing the pellet weight to 16 grains...
Ultimately, results on target are all that count; not theorists who sit at home, commenting on the real work performed by others. Keep up the good work.
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Sub, all theories will be tested to rule out negative possibilities as much as possible. for me, pellet or bullet. i still prefer the CG to be right at midline as a starting point. with swaging, you can vary this CG as you make different punches. i am sure casting makes adjusting the CG easier with different hollow pins provided. That way, we have control over how the pellet acts in flight, thus accuracy. if these are not accurate and we can't tweak it, then it's failure!
Ken, i see some differences in your punch design compared to HEN punches from China. I'll show it below, little machine can take care of it and doesn't effect CG and centroid much (also see posted pictures above). you can also find pellets from JSB also has this 90 degree inside step and still keep their skirt thickness to .026inch that is 0.66mm
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I might be confused, but isn't the lead bleed path at the OD step I added, shown in blue?
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no Sub,
That is the punch stop for it to touch the punching plate when hammering! I can even see the HEN punches sometimes stops too short and creating less of a 90 degree inside angle at the skirts. I am telling you KEN, i got eyes for little details man.
See the third picture Sub, the crossed white section is the punching plate on top of the cavities. the punching plate has hollow cavities underneath to allow for lead bleed, then sliced off with knife. either machine down little at the tip or the hole length of punching rod like shown
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Thanks, Duy. Makes perfect sense now.
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I Got the 90 degree step on the punch DarkCharisma, its 0.02 mm in length. just a little bit of machining will do it. I will make one today. Guys I am moving to tool steel and I am using EDM to make the new prototype, The S.S. is way too complex to machine (what I mean is that my reamer simply glides on surface and chips off small grains creating a bearing surface which is not uniform, with tool steel I will have a good amount of material to cut using reamer) . I measured the pellets the head size was 5.48 not 5.52 what I had designed, SO.... We are going EDM.. The combinations for EDM were tested yesterday and the first spark combination gives a predictable allowance of .XYZ mm. hence a tool can be designed accordingly. CNC is time consuming and tools don't last longer.
Sub I am using CAD to design and FEA to simulate results.
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Ken, you have some serious skills. That includes recognizing when to change paths, and move to something that should yield better results.
EDM will result in cavities that are slightly "frosty". The roughness that this texture imparts to the pellet may be of no consequence, although purist may prefer a smooth look. Roughness all over the pellet may reduce its overall drag, by creating small eddies in the manner that shark skin does. The roughness may also increase the Magnus effect; where the pellet is driven up or down by cross-winds.
Anyway, If you do have roughness that is of a large enough magnitude to make the pellets hard to remove from the die-halves, then a post EDM polishing process would be indicated. I don't know if anyone does electrochemical polishing of die cavities, but abrasive polishing should work fine - as long as it is applied evenly.
The bottom line is that you may have to EDM to a diameter that is perhaps 0.025 to 0.05 mm undersized to allow for polishing to final diameter.
I recognize that you are developing a process to create these dies. This involves room for what some may call, error. I don't see a learning step as error.
Once you have figured out your working recipe, making other dies, in other calibers and configurations should be easier and more profitable.
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As pellet roundness is important, you may need to rotate your EDM electrode slowly, as you burn the cavities.
Continuous electrode rotation should not be required, as the amount of steel eroded per spark event is small, and the electrode erosion even smaller. A play-less chuck that runs true, and has a ratchet mechanism to increment it springs to mind.
An incremental electrode rotation of perhaps 35 degrees, every so often should work. Just ensure that the increment does not divide evenly into 360 degrees, else you could end up with a "lobed" pellet. Ditto, the angular "timing" of continuous rotation with respect to the sequence of erosion events. Let the burn events and electrode rotation "phase slip" relative to each other, to evenly distribute any erosion unevenness.
Or you could make two sets of identical non-rotating electrodes; where the second set evens out the deviation in roundness, induced by erosion of the first...
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Sub, i have no idea how edm works, and their terminology. so are the processes you explained. do you have or work with EDM and may be able to produce some of these molds to possibly include a video of whats all involve in its operation?
Ken, good choice to go with Edm and tool steel. i have seen some very good products cut with EDM to tight tolerance at a local shop.
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Sub, Thats some serious info. I think that making 2 set of tools will prove to be effective with existing machine setup. I will post some pictures of the tool once its made (next few hours). Thanks for the info Subscriber.
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I wish I had my own EDM machine. Lots of youtube videos on making them at home. Of course, to erode metal accurately, the electrode stage has to move on precision rails, under backlash-less control; just like a decent CNC machine.
My EDM experience is indirect. The latest is related mostly to plastic injection mold manufacture; where I am the product architect, rather than the tooling or end product manufacturer.
That said; understanding what happens to EDM electrodes makes it easy to predict that the electrode will erode unevenly when you burn one die-half at a time; unless the electrode is rotated (or mitigating the effect by replacing it with one or more identical electrodes for a "finishing cuts" that are repeated at full depth).
If you finish eroding one pellet's "pocket" in the die-half, then move to the next, the last "pocket" will be measurably smaller than the first; due to electrode erosion. As you want all the pellets to measure the same, you want to burn each pocket partially, before moving to the next; and so on. That way, all pockets see about the same degree of electrode erosion and their diameters should be much closer together.
You can probably monitor electrode erosion by measuring the faces nearest the steel being cut, from time to time. That knowledge should enable you to implement an effective mitigation strategy.
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I Got the 90 degree step on the punch DarkCharisma, its 0.02 mm in length. just a little bit of machining will do it. I will make one today. Guys I am moving to tool steel and I am using EDM to make the new prototype, The S.S. is way too complex to machine (what I mean is that my reamer simply glides on surface and chips off small grains creating a bearing surface which is not uniform, with tool steel I will have a good amount of material to cut using reamer) . I measured the pellets the head size was 5.48 not 5.52 what I had designed, SO.... We are going EDM.. The combinations for EDM were tested yesterday and the first spark combination gives a predictable allowance of .XYZ mm. hence a tool can be designed accordingly. CNC is time consuming and tools don't last longer.
Sub I am using CAD to design and FEA to simulate results.
EDM is the cat's meow when it comes to precision on tool steel, that mold shop my brother helped put together bought a nice EDM a few years back, my brother even mentioned if I had everything ready as far as the Cad Cam(CNC for the mold block) part goes that I could get them to make something at a very reasonable price. He even said that most everything that he's been doing in that shop recently has been prototype stuff.
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Info on rotating EDM electrodes:
https://www.researchgate.net/profile/Janak_Valaki_phd/publication/284443119_DEVELOPMENT_OF_A_MICROCONTROLLER_BASED_ROTATING_ELECTRODE_ATTACHMENT_FOR_RAM_TYPE_ELECTRO_DISCHARGE_MACHINE/links/56533fba08ae1ef92975eba6/DEVELOPMENT-OF-A-MICROCONTROLLER-BASED-ROTATING-ELECTRODE-ATTACHMENT-FOR-RAM-TYPE-ELECTRO-DISCHARGE-MACHINE.pdf (https://www.researchgate.net/profile/Janak_Valaki_phd/publication/284443119_DEVELOPMENT_OF_A_MICROCONTROLLER_BASED_ROTATING_ELECTRODE_ATTACHMENT_FOR_RAM_TYPE_ELECTRO_DISCHARGE_MACHINE/links/56533fba08ae1ef92975eba6/DEVELOPMENT-OF-A-MICROCONTROLLER-BASED-ROTATING-ELECTRODE-ATTACHMENT-FOR-RAM-TYPE-ELECTRO-DISCHARGE-MACHINE.pdf)
https://www.youtube.com/watch?v=9KwR4zF-Uxw (https://www.youtube.com/watch?v=9KwR4zF-Uxw)
Basic operation of sinker EDM. For the pellet dies, the sinking would be "sideways", rather than down:
https://www.youtube.com/watch?v=_v1rm7a3-6s (https://www.youtube.com/watch?v=_v1rm7a3-6s)
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my brother even mentioned if I had everything ready as far as the Cad Cam(CNC for the mold block) part goes that I could get them to make something at a very reasonable price. He even said that most everything that he's been doing in that shop recently has been prototype stuff.
Wayne, i like the sound of that...reasonable price. can ya tell your brother to actually make one?
Really neat stuff Sub
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Subscriber, that's a terrific cost effective solution. I have both the Arduino and the geared motor along with its drive. This is gonna be my next project after completing EDM sinking sideways. I am thinking of automating the self centering vise or chuck using a IP67 servo motor. The pic of EDM tool (I removed it from the forum, obvious reasons, anyways PM me if anyone wants a pic)
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I would probably go over to the shop and talk to the owner myself, he's a friend, he lets us (my brother has keys to the place) use his shop. My brother is a retired journeyman mold maker himself.
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Ken can you burn a lot of cavities with just the one electrode you make? I personally don't know much about them, my brother has talked about them quite a bit though.
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Electrode VS job erosion rates, and surface finish achieved at different current settings and pulse duration:
http://iopscience.iop.org/article/10.1088/1757-899X/50/1/012062/pdf (http://iopscience.iop.org/article/10.1088/1757-899X/50/1/012062/pdf)
Designing electrodes. Including compensation for "over-burn" (hole larger than electrode):
https://www.theseus.fi/bitstream/handle/10024/86204/Thesis-Bishwas.pdf?sequence=1 (https://www.theseus.fi/bitstream/handle/10024/86204/Thesis-Bishwas.pdf?sequence=1)
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Wayne, The tool wear gets accelerated over series of operations, hence a set of identical tools have to be made (that's what the EDM technician said), So I have made a total of 12 tools where 6 have a .XY offset to compensate for erosion and other 6 have .XZ offset. Sub. Thanks for the research papers, I’m humbled and appreciative for all you’ve done. Tomorrow I will get things tried and tested on EDM.
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Ken. Only too glad, if I can be of any help.
Exact diameter and roundness of the pellet heads and skirts are the most important aspects. As such, it would seem to me that those aspects should be "burnt" to finished dimensions, last. That way, the last electrodes you use will already have clearance with the cavities in the less important dimensions.
Based on the papers I linked, finishing should be done at lower current, to achieve a smoother finish, and to slow electrode erosion to produce a more exact cavity.
That said, my goal is only to provide food for thought. An experienced EDM guy should know the answer to all these questions; or should know how to determine them.
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Sub. you mention you want your owm edm machine. i am sure you can get online and find some used one as a base to work with. they are currently under 10k
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Sub. you mention you want your owm edm machine. i am sure you can get online and find some used one as a base to work with. they are currently under 10k
I'll take two :)
Ken has been quiet. Either he is very busy; or he has stopped...
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I was figuring out what went wrong on first attempt. Though the pellets were perfect round head diabolo but the head diameter was not upto the mark. I revisited my EDM technician and figured out the size for rough pass and Final finish. I tested with a 5.40 mm tool and got 5.403mm cavity on the correct current, Now I know what it takes to make a perfect 5.50mm-5.51mm-5.52mm heads. Tomorrow I will try to score the perfect Home run with a 5.5XYZ mm head. Thanks sub. the research papers helped.
By friday I will work on .25 and .22 moulds. Will keep on posting about the progress from Friday, so tomorrow I will be busy making blueprints and CAM co-ordinates for drilling some guide holes.
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This has been an interesting thread to follow. Looking forward to seeing how this pans out, Ken!
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I'll take two :)
Ken has been quiet. Either he is very busy; or he has stopped...
I wish i'd know everything about CAD and EDM, i'd jump at some deals on ebay even...i might even settle for manual instead of CNC EDM...lol EDM on ebay is dirt cheap.
Ken, i know you been busy. don't forget to update us on Friday
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That's definitely some very cool stuff you going on there Ken!!! Every time I see a new post on this thread I'm right on it.
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Friday update: Tool steel from Germany has arrived. It will form the mould core. Right now its getting machined (Milling and surface grinding). as of now I am making 2 versions now in .25 caliber. a custom slug 50 grains and a 40...ish grain .417" long round head diabolo. I managed to make .22 in 5.52mm head but the test material (S.S.) was fighting back because its not magnetic and EDM tool simply wears out due to arcing making other 4 cavities smaller and smaller. So .25 is bigger and new material is perfectly suited for EDM operations. making 2 moulds in a shift saves $$ and time.
Other thing. as Sub. said EDM makes grainy texture, I couldn't find a polishing process that will guarantee me "Consistent" MRR for smooth finish. It wont be any problem for swaging, but it will be of some issue with casting. (which is not a swager is intended to be). I will get around the .22 but with 30-32 grain design that fits most of the mags.
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Ken, if the texture is fine enough, think of it as engineered to hold just the right amount of lube. :)
If the finish is too rough, both swaged and cast pellets may battle to come out of the mold half, requiring so much persuasion that they may get some marks on the pellets.
Remember, reducing the current improves surface finish, because each micro pit burnt is smaller. You might try that on your finishing burns. One of those papers gave comparative current and time values.
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Sub. I got it. the machine here is slightly different so some tweaks in settings will be just fine to produce fine and even grainy texture.
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Saturday update:
1. Milling and sizing of block's is complete.
2. Blocks have been drilled and will be ready for EDM by Tuesday.
3. New .25 punch are getting ready ETA Monday
Things are going slow and steady,I double check every step to assure that errors in previous attempts don't repeat this time.
Estimated time of completion will be somewhere on Wednesday or Thursday.
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Thanks for the update , Ken.
What kind of steel are the blocks? In what conditions / hardness?
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Hello, Ive been busy scrambling all my resources to make the tool steel swaging Die (its not a mould Now). The block is partially machined and is ready for hardening before going EDM. Tomorrow the remaining machining process will get completed especially reaming the guide holes to match the parting lines. Other ancillary parts like punch and guide plate is getting machined as I write this update, So far so good.
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Looks good Ken.
Sub, I think he's working on some german alloy steel. I have not been able to get a the exact name but somewhere around A2 composition. P20 is a good start or even better with S7. But steel grades in other parts of the worlds are also different. I have been working one swaging dies with o1 steel and i like it.
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Looking good, Ken!
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made some dies out of o1 to test precision reaming. a little undersized
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Update. The Blocks are ready for EDM, Its taking time to finalize the EDM settings as the new batch of copper electrodes have slightly different composition hence they wear out quite a bit. I had to refer to 15 research papers in this week to figure out the current. Ive achieved 95% Diabolo shape the last 5% is creating issues. Going in for another go on monday. Things seem like a cold start ( https://www.youtube.com/watch?v=1nGUMTMLsvE (https://www.youtube.com/watch?v=1nGUMTMLsvE) )
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Ken I had a 65 Chrysler Newyorker many moons ago, wish I had one in the same shape that one was.
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Good job, Ken
Any pictures you can share?
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havent seen any updates and i am eager. my huben k1 .25 didnt like the casted pellets and bullets from NOE. so i made my own swaging dies. slow to produce but works. shooting 1/2 at 20 yards with authority. 56grains going at 830fps average, max 870fps. hope everything is going well over there Ken.
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I am back with another update. Today I tested new batch of electrodes, for a head diameter for 5.50mm, The tool wear was studied for rough pass and finish pass. and results are consistent. I casted some pellets for head size. I am waiting for my lead wire to arrive so that I can test swaging with my press. Casting may not produce consistent results because my Die has no venting lines like Noe. I think that 97% of progress is made. Tomorrow I will go for 3rd finishing pass to check tool wear and compensate accordingly for .25 Slug cavity.
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looks good Ken, keep em coming. lets move onto the next stage.
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Jolly good, Ken!
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I was busy for some time 8). so I made 3-4 different types of swaging die's. Some succeeded some failed. So I went ahead on DarkCharisma suggestion and made some Slug moulds. Cast and swage out of Hot die tool steel. A new variant is ready I am testing it for casting and swaging. I will upload some images soon but here is the sneak peek of the block before machining. This block can accommodate 7 slugs on each side making it total of 14 slugs. Since its made of hardened tool steel it wont rust easily and will last longer than any conventional mould.
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And its made. 7 slugs and 7 pellets.
40-grain slugs
46.5-grain pellets
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Next project is a .217" slug swager for FX slug X duties. .303 long and 27 grain. And a .22 - 36-grain pellet. More lead per sq-in, High BC that's what we call em.
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Ken, that is simply brilliant!
For anyone thinking they would prefer shiny pellets, try zooming the images out until they are life-size on your screen. The life-size texture is so fine that it will probably reduce pellet drag, rather than increase it; by forming small eddies like shark skin or dimples on a golf ball.
One of the posters on GTA obtains very good results from knurling slugs to bump up their diameter. The resulting "gross roughness" may not add to accuracy or range, but it certainly isn't hurting it. What matters with Ken's projectiles is how they shoot. He should find volunteers here to test them for him.
Looking forward to seeing progress with your other calibers too, Ken.
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One aspect of Ken's dies is that these are "cast and swage" dies, similar to those demonstrated in the video below.
I prefer the "cut wire to length and swage" approach. However, if all you have is scrap lead, or pellets from a trap, then casting the "blank pellets" in situ is certainly a viable approach.
https://www.youtube.com/watch?v=Ry9y-cXlCC0 (https://www.youtube.com/watch?v=Ry9y-cXlCC0)
Try to look past the die whacking with a hard hammer, and dropping the dies onto concrete, as shown in the video. The creator (not Ken) is trying to show how simple and fast the operations are, rather than demonstrate best practices to prolong die life, and to keep grit out of your pellets (and barrel). This demo would have been better with a mallet, on a clean wood table...
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Absolutely, Subscriber.
- The purpose of a swaging kit is to have the ability to recycle your used pellets from the trap or to reuse lead from other sources like wheel weights etc.
- Its something that can be your activity where on an average 14 pellets can be made under 2 minutes hence complementing your available bullet casting
and reloading setup - Swaging can be your only option if access to quality pellets is not available
Casting and swaging is the way to go because it enables lead to flow in the cavities and by swaging, stamping, punching it in cavities makes it to occupy the space and get the shape (unlike wire swaging where 3.25 and 3.75 mm wire is required for a single.22 cal pellet with different head shape eg 3.25 for 18 grain and 3.75 for 24 grain). If the pellets are not swaged then you will get shiny cast bullets which are smaller in diameter (lead shrinkage).
I've shipped the mould to Texas so volunteers are welcome to test it. The dimples on the pellet are not so pronounced to the naked eye. They may aid in stability in winds because of the Fluid boundary layer separation theory used in Golf ball design. When things go sonic smooth surface reduces the drag but when things are subsonic then surface roughness aids in stability because air tends to stick to the surface and generate the "Essential" drag for drag stabilized pellets. Yet it needs volunteers to test it.
Whacking the Mould is not the appropriate way to extract the pellets, gently tapping on sides will release them. These moulds are made up of hot die steel and hardened hence they will not deform like brass and aluminium moulds used for casting (I think a 4 cavity casting only mould for slugs/bullets made out of hardened tool steel will cost under $110 8) ). Yet a wooden mallet, clean surface and safety gear is essential because the surface is hot and sharp tools like planer blades or paper cutters are used.
That's it, Any other suggestions, Questions, topics are welcome.
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when you get around to making bullet casting molds, i will be the first to order Ken. i cannot wait for casting molds in steel...i prefer steel. a little care for storage but will last a while longer than malleable moulds. post some steel casting molds pictures here when you get to it.
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.i prefer steel.
Ken's molds are made from hardened steel...
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.i prefer steel.
Ken's molds are made from hardened steel...
Its Hardened hot work tool steel country of origin: Germany.
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yes Sub, i been trying to find casting molds that are steel. hard around here
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Hi Ken and Duy
Duy the pics on the rounds made from the NOE molds look pretty bad those I would cull... if they all look like that well you need to work on your casting skills a bit... the skirt of the pellet is very important and needs very to be near perfect.... The BBT 40g looks to be a touch wrinkled and like with a pellet the base is very important... also they will need sized for the barrel...
Ken looking at the design of the pellet my gut say it should do well from about 60 fpe up but once again execution is every thing and you have to make sure the skirt is perfect... in the slugs close and pellet close pics it looks as if the bases are not level...that kills accuracy...
There is a bit of a learning curve to casting and molds... one of the many things is keeping heat in the mold and keeping it steady thru casting pace... mold and spru plate design matter also... heck on the BBT 40g mold I was getting bases that were slightly rounded on one side...it needed a slightly smaller sprue hole to cast nice sharp bases... was allowing the sprue puddle while cooling to pull from the base causing shrink at the edge... Al (NOE) sent me a .125 sprue hole plate to replace the .140" plate and it fixed the problem...
how hot you run your melt and your mold matters... how big(compared to the rounds being cast) and what material the mold is also matters...
there is a lot to get right...
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K.O the Images were clicked on random, to test different punches for different weights and style. here is a pic of the pellets with the thin skirt to aid expansion and engage the rifling. Good observation over there. If you see the video you can see the person shaving off the excess lead (I didn't perform that step because the planing blade was blunt)
Regarding casting, I tried to make the sprue holes to .118" and it didn't work so I made them to.155" and it made the difference, and .155 allows more lead to flow before it cools off and chokes the sprue
The beauty of my mold is that you can use a punch to force the lead to occupy the entire cavity. So a not so uniform cast pellet, the bullet can be made uniform with the stroke of a mallet or through arbor press. Its different than aluminum or brass molds (Mine is Die steel ) where you have to tweak the temperature & make some adjustments to get a proper fill, In my case, an Improper fill will be made into fine pellet because of punch bleeding the excess lead out of the skirt cavity(planing it off later). I will be making a video for the procedure but it's nearly identical to the one posted by Subscriber.
Its a Die that works on cast + swage process of making the pellets or slugs. Ideally, a wire is used but It costs upwards of $25 for a spool, so Ive made it in such a way that, an average airgunner, bullet reloader can reuse the range scrap and make useful pellets, slugs out of it. It's as easy as that video.
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Went back and read the whole thread makes more sense now... those look much better... still would try and get them cast as perfect as possible before swaging just for that last little bit of consistency... hope they shoot well... the similar BBT seem to... the slightly hollow base and fuller round nose are about the main difference that will/may move the Cg forwards just a touch...
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it does look more involved than making the BBT 40g... and also with the pellet once you get the pins set right on the Noe mold...that is a touch fiddly... My stock Mrod does .75 at 50 with the 40g BBT when sized to .2495-.250 at about 750 fps...the 34g pellet did well also despite a bad transfer port oring...
Hope testing goes well.. ;D a 45 grain Super Magnum pellet.. 8)
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it does look more involved than making the BBT 40g... and also with the pellet once you get the pins set right on the Noe mold...that is a touch fiddly... My stock Mrod does .75 at 50 with the 40g BBT when sized to .2495-.250 at about 750 fps...the 34g pellet did well also despite a bad transfer port oring...
Hope testing goes well.. ;D a 45 grain Super Magnum pellet.. 8)
My casting skill is no where near any where like people on GTA. but i have bought a new lee bottom pour pot. man that thing pours like a giant ^*%$#@ hot molten lead. and the result is very very good!!! The old pot was pouring slow, maybe that's part of the problem i had.
Yah, I am ready to send out some batches to beta testers...I cannot wait to hear results back...the pellets are a bit rough but i think it will do just find acting as a bullet when driven above 950fps.
Thanks for the data on the BBT 40 grains. I think i should size down to .250 to test it out again
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A new mould is made and ready. It was as per Dark Charismas requirement of a Heavy pellet in 22 cal. The heaviest one being 33.9-grain JSB. So I made a 36-grain pellet 0.421 long. 5.52 head. I think the airforce condor in .22 will like them. It also houses 3... 40-grain meplat .25 pellets (Images will be posted after I resize the Hd images to 100kb jpg format). The design for .217 slugs is ready but I am aiming for the .357 light and .357 Heavy in 70 and 88 grain. long enough to fit any mag and versatile enough to suit any gun high or low powered. Anyone Interested?
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yep i have a .22 condor, it may like it...so the .217 slugs is how long at 70 grains?
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yep i have a .22 condor, it may like it...so the .217 slugs is how long at 70 grains?
.357 light and .357 Heavy in 70 and 88 grain
Looks like the light .357 is 70 grains; not the .22...
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The heavy 0.217" pellet is 36 gr....
Bob
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The images are close Macro shots. Some pics of other popular pellets. (https://www.crosman-air-pistol-owners-forum.com/board/index.php/topic,637.0.html?PHPSESSID=pgoq75vbtfcd50oavr3tg390t5 (https://www.crosman-air-pistol-owners-forum.com/board/index.php/topic,637.0.html?PHPSESSID=pgoq75vbtfcd50oavr3tg390t5)) suggested by the subscriber.
Edit: the pellets are 5.527mm and 6.36 mm in diameter all around, these pellets are not cleaned hence the parting looks pronounced. They are straight out of the mould. The cleaning operation is not done.
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I like the looks of that Ken. I am interested to see the .357 light and heavy on your mold.
Going to send you some of Bobs design for .177 cal, 20 cal, 30 cal and 35 cal.
I really like the metplat pellet from Bobs design. going to test that out
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https://www.youtube.com/watch?v=KEIf1cCajJU (https://www.youtube.com/watch?v=KEIf1cCajJU)
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The kit looks really good. Thanks for taking the time to make the video!
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Thanks, It was undergoing tests so I made a video of it. The mold will be commercially available and will be priced similar to some good casting molds. The swaging setup will cost sub $400 with the mold, press, and tools (tools from Amazon). Same as buying 2 brass casting molds. Molds will be available through an exclusive dealer network soon.
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.30 and .357 are getting ready. They weigh in at 60 grain in 30 and 102 grain in 357. Designs are made by simulating the pellet through a Lothar Walther barrel and checking it for friction areas around the pellet. Skirts are designed to deform in areas seen visibly engaged. A lot of engineering is involved in making the latest and most advanced moulds to date. Will be released soon for under $399 (shipping included) through dealers in Texas and other states.
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The kit looks really good. Thanks for taking the time to make the video!
Thanks, Sharpshooter Chako, 2 more videos are planned. stay tuned
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wow looks really good I was try here in Chile create molds, but are very expensive the development, if u sell in .22 and .25 I and friends will buy definitely ur molds
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here other option , from russia with love ;D
https://forum.guns.ru/forummessage/370/2016015.html
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Thanks dude, The Russians make really good swaging dies, lot to learn from them. What about Chile? whats the issue with .22 or .25 pellets out there? are they expensive, Banned or arent avaliable?
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Thanks dude, The Russians make really good swaging dies, lot to learn from them. What about Chile? whats the issue with .22 or .25 pellets out there? are they expensive, Banned or arent avaliable?
Hi ken , here in Chile the airgun world are very basic, there are not engineer development in this field, I think I'm the only one. Here the pellets are expensive and more in larger caliber that is why i tried build molds to obtain high quality pellets with high BC, but is very dificult with clasic tools.
because these i search options to obtain good molds but at reasonable price. now exist the Russian and u ;D
Im fan of high power airguns ,slugs with high CB and long range shoots. My dream is build a rifle as a "tale of three brod" and use cast/swaged pellets
Im very near to be engineer and have many desings of complete airguns based in rsterne builds and personal desings but here in Chile dont have aluminum tubes or plates, Cromoly tubes .....is very dificult buy these materials. barrels are imposible
greetings ken
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Those Russian dies look beautiful on the outside and seem to make nice projectiles (based on the images).
A shortage of barrels is a problem. Perhaps someone might be motivated to make some in Chile (assuming it is legal). Alibaba have both unrifled chrome-moly "hydraulic tubing" for sale, and rifling buttons; from various suppliers.
For instance, these buttons are sold as "reamers": https://www.aliexpress.com/item/6-Flutes-Spiral-Reamer-5-81-9-35mm-Push-Rifling-Buttons-Double-Layer-Blade-Reamer-for/32921843699.html (https://www.aliexpress.com/item/6-Flutes-Spiral-Reamer-5-81-9-35mm-Push-Rifling-Buttons-Double-Layer-Blade-Reamer-for/32921843699.html)
Unrifled barrel blanks https://www.aliexpress.com/item/seamless-steel-pipe-OD-12-mm-long-50cm-tube-steel-Hydraulic-40cr-chromium-molybdenum-alloy/32872237301.html (https://www.aliexpress.com/item/seamless-steel-pipe-OD-12-mm-long-50cm-tube-steel-Hydraulic-40cr-chromium-molybdenum-alloy/32872237301.html)
This is a licenced gun manufacturer that develop unusual guns. Here he makes good barrels as simply as possible:
https://www.youtube.com/watch?v=gtLYnqZQHCY (https://www.youtube.com/watch?v=gtLYnqZQHCY)
This second guy makes rifled barrels with crude tools, just to prove he can do it. He has a number of videos at this link: https://www.youtube.com/results?search_query=idahoan+rifling (https://www.youtube.com/results?search_query=idahoan+rifling)
Certainly, pulling a button through a rifle barrel is better than pushing it, due to the tendency for long driving rods to buckle under compression, and straighten under tension. Push buttons are more appropriate for short large caliber barrels. If operating at such force levels is a problem, there are many people on YT showing off their home made sinebar or spiral guide mandrel cut rifling machines.
For instance (one each of a series of these videos shown as a sample):
https://www.youtube.com/watch?v=orAi33HjWB8 (https://www.youtube.com/watch?v=orAi33HjWB8)
https://www.youtube.com/watch?v=0AKW-K4RyXo (https://www.youtube.com/watch?v=0AKW-K4RyXo)
Back to Ken's swaging equipment, after that interruption...
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Those Russian dies look beautiful on the outside and seem to make nice projectiles (based on the images).
A shortage of barrels is a problem. Perhaps someone might be motivated to make some in Chile (assuming it is legal). Alibaba have both unrifled chrome-moly "hydraulic tubing" for sale, and rifling buttons; from various suppliers.
For instance, these buttons are sold as "reamers": https://www.aliexpress.com/item/6-Flutes-Spiral-Reamer-5-81-9-35mm-Push-Rifling-Buttons-Double-Layer-Blade-Reamer-for/32921843699.html (https://www.aliexpress.com/item/6-Flutes-Spiral-Reamer-5-81-9-35mm-Push-Rifling-Buttons-Double-Layer-Blade-Reamer-for/32921843699.html)
Unrifled barrel blanks https://www.aliexpress.com/item/seamless-steel-pipe-OD-12-mm-long-50cm-tube-steel-Hydraulic-40cr-chromium-molybdenum-alloy/32872237301.html (https://www.aliexpress.com/item/seamless-steel-pipe-OD-12-mm-long-50cm-tube-steel-Hydraulic-40cr-chromium-molybdenum-alloy/32872237301.html)
This is a licenced gun manufacturer that develop unusual guns. Here he makes good barrels as simply as possible:
https://www.youtube.com/watch?v=gtLYnqZQHCY (https://www.youtube.com/watch?v=gtLYnqZQHCY)
This second guy makes rifled barrels with crude tools, just to prove he can do it. He has a number of videos at this link: https://www.youtube.com/results?search_query=idahoan+rifling (https://www.youtube.com/results?search_query=idahoan+rifling)
Certainly, pulling a button through a rifle barrel is better than pushing it, due to the tendency for long driving rods to buckle under compression, and straighten under tension. Push buttons are more appropriate for short large caliber barrels. If operating at such force levels is a problem, there are many people on YT showing off their home made sinebar or spiral guide mandrel cut rifling machines.
For instance (one each of a series of these videos shown as a sample):
https://www.youtube.com/watch?v=orAi33HjWB8 (https://www.youtube.com/watch?v=orAi33HjWB8)
https://www.youtube.com/watch?v=0AKW-K4RyXo (https://www.youtube.com/watch?v=0AKW-K4RyXo)
Back to Ken's swaging equipment, after that interruption...
A long time ago I have in my workshop the idea of a machine to make barrels, I found a Chinese supplier of the necessary tools.
https://www.ebay.com/usr/riflingbutton?_trksid=p2047675.l2559 (https://www.ebay.com/usr/riflingbutton?_trksid=p2047675.l2559)
soon I will start its construction, but the difficult thing is to find the tubes of Cromoly with the correct internal diameter
regards
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WOOHOO, 3200 views. That's a lot of attention. I would like you guys to know that something great is happening. Look at the finish of our machined .30 cal test cavity. (next to it is our 1st EDM cavity that started it all). What do you think of it? Group buys?
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Smooth!
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Hey guys, I am finally back from Asia, but also loaded with chores and moving to a new flat. I have not been able to get on or touch the swaging dies at all. But i am slowly getting to it. Ken has started on the new process similar to CNC, which i wanted to begin with since the beginning. Sub, I am still working on producing pellets for the masses, hopefully i can ship before Christmas.
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WOOHOO, 3200 views. That's a lot of attention. I would like you guys to know that something great is happening. Look at the finish of our machined .30 cal test cavity. (next to it is our 1st EDM cavity that started it all). What do you think of it? Group buys?
Wow looks really good!! ken I will start saving money, if everything is going well I would like to represent you here in Chile
Regards
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This is It. We have achieved the results. Super macro pics of parts, you can see the microfibers of cotton in some pics. Comparison of our commercially available pellet mold vs prototype. A sub $399 SWAGING mold is now accessible to masses, with 6 cavity Hardened TOOL STEEL mold starting from $270 effectively costing $45 per cavity and 10 cavity mold at $350 effectively costing $35 per cavity. RIP Aluminium and brass molds ( Casting molds made from hardened steel coming soon )
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Looking good, Ken
Can you explain the polished VS matte looking cavities? I assume it is to show off your latest process :)
In other words, what does one get for the money, and how does one use it? Pellets coming out of the shiny cavities should look nicer too.
It would be great if you showed measurements for the pellets, taken across each cavity split line, and parallel to each cavity, from a given block.
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Sure, sub. I am in the process of making such a video where the details of the new mould will be shared.
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This is what happened at the heat treatment facility, They said, Sir if its aluminium then it will melt, I replied: No its tool steel. Make it as hard as 57 HRC, they replied: At that hardness, we think that you can use your mould as a tool to cut aluminium. ;D .
The results are stunning after getting the mould hardened.
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Looks very nice, Ken!
Is the tool steel hardened before or after you make the pellet cavities? Is this EDM, and then abrasive polishing; or a completely new secret process?
The only aspects that really matter to us are pellet diameter, roundness, concentrically, weight and consistency between cavities. Certainly, shinier pellets are prettier; but roughness of the cavity matters mostly with respect to getting the pellets out of the cavities undamaged.
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Sub. I've turned to Mill it out on the new Makino VMC. I used fine cutters to cut the profile. I have mastered both the EDM and CNC milling techniques and Milling seems to be a perfect choice. The blocks were at HRC 20 and were machined using profile cutters. later hardened. It is consistent in diameter 9.04 to be precise. Pellet extraction has become easier now unlike those micro-pits of EDM, the surface is smooth and uniform.
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That is great, Ken
Unless this is air hardening tool steel, or you had it nitrided, the typical problem with machining to final dimensions before quench hardening is distortion due to the rapid cooling. If your die-halves stay flat and the alignment pins don't fight, than chances are that the pellet cavities are good with respect to alignment and roundness too.
Can't wait to see some pellets from these dies.
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for the type of steel that is being used...20hrc would have been minimally adequate at a cost of shorter life. we can't discuss the make up of the type but it is air hardening. i can see induction harden a very fitting method for it. lets jump into induction next Ken.
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Air hardening steel is good for minimizing distortion, because no quenching in water or oil is required. Pretty expensive material, but great for this application.
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Yes they are air hardened, And they shine really well.
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Nice!
Any diameter / roundness measurement data you could share?
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Yes, the .357 measure 9.04 on the head and .30 measure 7.69mm on the micrometre. .30 is made specifically for LW barrel.
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what are the weight variables?
parting lines are a bit noticeable...i hope that doesn't foul play on accuracy beyond 75 yards. Another improvement Ken! bravo, love the shine, must be very easy to extract?
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Even the dust particles look bigger. Finishing off a .25 cavity with super macro pics.
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Even the dust particles look bigger. Finishing off a .25 cavity with super macro pics.
I think that results are awesome!, But before buying a mold I would like to try some pellets and see groups that can achieve
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8 pages of reading lead to a dead end? Inquiring minds want to know, how does this all end? Hopefully with molds becoming available for sale.....
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Ken and I went separate ways. he is no longer making pellet dies. it was impractical and very expensive and time consuming for both of us. i wait forever to get one mold done and he has problems setting up with the machinists over seas.
i think he's focusing on slug dies. why don't you ask him?
i have pellet molds but they are expensive...
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I may catch grief for this, but how much is "expensive" for a swage mold, and which mold would it be? I might be interested in a .22 (others may benefit from the response. ;)
Thanks,
M
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I may catch grief for this, but how much is "expensive" for a swage mold, and which mold would it be? I might be interested in a .22 (others may benefit from the response. ;)
Thanks,
M
i paid $350-$400 per mold on average that was shipped to me. the molds are made out of tool steel and hardened. all my molds swages heavier pellets, so in .22 is 36 grains...been a while but its more than 34grains
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Hmmm, not too bad for a lifetime supply of pellets, or at least the potential to make your own. Though $350 would buy approximately 6500 ..22 pellets, for most that would be a lifetime supply. Still the ability and the satisfaction of making your own is very satisfying.
How do the pellets made out of your molds shoot compared to factory pellets? (loaded question ;)
Cheers,
M
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i have not shot any of them myself past 25 yards. i have sent to several people in this forum but only two responded. Knife from TX and James from FL. Knife reported spiraling after 50 yards. James reported under 3/4 inch at 50 yards at +90fpe and inconclusive at 100yards when he ran out of pellets. this is the 44 grains 25 caliber...very limited testing
this type of mold takes longer to make pellets and having sent to more than 6 guys to test but only 2 reported got me discouraged fast. i then focused on slug molds but put it on halt since i got too busy with other projects.
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Also found this post from another guy that is making pellet molds, he charges a little more and his molds are not hardened but it seems to be well made with more cavities. his is 20 cavities compared to 10 cavities i have.
https://www.gatewaytoairguns.org/GTA/index.php?topic=164388.msg155834513#msg155834513 (https://www.gatewaytoairguns.org/GTA/index.php?topic=164388.msg155834513#msg155834513)