GTA
All Springer/NP/PCP Air Gun Discussion General => Machine Shop Talk & AG Parts Machining => Show Off Your Air Guns With Mods (SHOW and TELL) => Topic started by: MJP on August 08, 2017, 07:47:33 AM
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Stuff is hidden inside metal bars, you just need to dig it out of there.
This part of the job is not my favorite, drilling long holes.
(http://i2.aijaa.com/m/00188/14432052.jpg) (http://aijaa.com/pR3hYP)
Marko
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Barrel turning, breach end.
(http://i6.aijaa.com/m/00686/14432495.jpg) (http://aijaa.com/ggxq6y)
Marko
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How long of a barrel is it and may I ask what you're going to use for broaching the rifling ??? Wish I had access to some good machines myself I'd be going hog wild these days.
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Oh sorry Wayne, should have explained better, I was drilling the breech blank. Barrel is ready made match barrel.
Couple of more pics on work done today.
(http://i7.aijaa.com/m/00419/14433491.jpg) (http://aijaa.com/vQpUaj)
(http://i2.aijaa.com/m/00094/14433492.jpg) (http://aijaa.com/CdtuLf)
Marko
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Nicely done.
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Do you design your guns first or just make some parts and see if they fit? Looks very purposeful, what kind of power levels you're after?
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If you are asking do I make drawings first then yes and no. I have been a prototype machinists and making a lot of one off pieces, usually something broken and no prints or a napkin drawning brought to me.
I design it in my head, I can see the picture and how it goes together. But usually too lazy to actually turn on the confuser and cad something out.
I know and remember the dimensions I need, and just program that at the cnc, I dont have a atc on my machine so I usually go by one phase and one tool kind of principle.
Mostly have used mazatrol for programming and no cads available on what I did at work so I have not used cad and cam so much that it would speed things up.
But that all about to change this fall, I'm starting mechanical engineering studies.
Well power levels are around 300J on the last .223 so about the same on this one, but I made the upper completely diffrent, I want a detachable lock for easier cleaning.
Marko
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Something about shiny metal is sexy!
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You do nice work Marko, like the look of your receiver.
Curious about the step machined onto the barrel. Machining the bolt locking lugs onto the barrel? If so....cool idea. 8)
Al
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Thanks Al, you think pretty much the same way I do, yes locking lugs are going to be machined on the
barrel.
And detachable cocking pin on the bolt so it can be removed easily.
I'll post more pics when I'll get more done, thunderstorm today so dont dare to risk my cnc controller and drives.
Marko
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Very cool idea Marko. Makes a lot of sense, and as far as I can recall, it's something I've never seen used on an airgun before.
Will await the pics... :D
Al
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One more phase done, tube radius to the bottom of the receiver.
Now I'm at the point where CAD would be helpfull, but still too lazy to use it, so sharpie and calipers it is. ::)
(http://i5.aijaa.com/m/00620/14436574.jpg) (http://aijaa.com/QL1Eka)
Marko
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Looks great so far!!! Can't wait to see the finished gun.
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Thanks Matthew,
You and me both, there is some new features designed and this is the first time I'm testing the ideas so it will be very interesting.
Marko
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Napkin cad, sharpies and calipers seem to be doing just fine IMHO. 8)
Al
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Thanks Al. 8)
Well now that engineering school started I dont have as much spare time, need time with the kids also. So progress will be slower from now on. Sorry about that.
Marko
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I've been silently following all of your projects, Marko (with great admiration, I might add 8)) and have to say....no apologies required! Family should always come first.
Besides....you just can't rush perfection! ;)
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Thanks Todd,
Well its kind of apologize to me aswell, I want to see this one group. There is so much new features that its either a winner or a complete washout. It should by all standards be perfect but you never know until you squeeze that trigger.
Marko
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It will still be there tomorrow to work on....only get one chance to watch the kids grow up.
Believe this one is going to be all winner Marko. :)
Al
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Not again.....What's in the water up/over there? I can no longer call myself a machinist, I am now just a hack, maybe if I move to Finland I will learn how to be a machinist? LOL not even that would help. Another fine piece of work from your area of the world. Beautiful women, beautiful guns, beautiful country but.....I hate fish.3 for 4 is pretty good in my book.
Pat
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Thanks Pat,
Maybe it is the fish. ;D
Time, wish I had more time to finish this one. Well it'll be done before the next season starts. That's a promise.
Marko
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And another holdup showed up to my shop, it was too good to let this one go by. ::)
(http://i6.aijaa.com/m/00277/14494701.jpg) (http://aijaa.com/SaLngo)
Marko
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Nice little Emco. 8) Quite sure I would have brought it home too. ;)
Interesting times ahead....
Al
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CNC Lathe?.... Lucky sod....
Bob
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You bet...a wee one...but a good size for valve parts. 8)
https://www.youtube.com/watch?v=3wvToHF1g0w (https://www.youtube.com/watch?v=3wvToHF1g0w)
Al
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Thanks guys!
Well valve parts where in mind when I saw this one, was browsing for lathe tools, and this popped up.
Was for sale at scrapmetal price so I didn't think for a second and just bought it.
Control pc had a broken hard drive, managed to salvage the WinNC folder and machine data.
Got wiring diagram and parts diagram from Emco yesterday, and I need to get the parts changer robot arm off the control logic. Its messing with the automatic chuck drive.
It was a production machine for one company that went under, was used to make plastic gears and nozzles.
Marko
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So sidetracking this a bit more, electronics work. Spindle bearings are shot, ways need grinding but she moves. Not bad for what I paid for it. :D
https://youtu.be/LtlLIQmkBFY (https://youtu.be/LtlLIQmkBFY)
Marko
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Fixable. 8)
Nice addition to the shop.
Al
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Should be quite an easy fix, the bed fits on my mill and it has a tilting head, I can fix the ways myself.
Need to measure how much the saddle has worn from the v groove, I was thinking about milling a slot and making a new v out of brass bearing stock. Shimming it in place and securing with setscrews.
Time will tell, how I go about it, depends how worn everything is. All of this would have been avoided if the previous operator had filled the oiler when empty.
I might make a new thread about the machine, maybe.
Marko
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Wow, took much more time to get back to this project than I thought. Luckily the Emco is up and running good :D
Did finally manage to find time to make some barrel ports.
(https://aijaa.com/img/m/00040/14546716.jpg) (https://aijaa.com/XOQUy2)
Marko
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Nice bit of machining.... so does the Emco work as a 4-axis mill as well as a lathe?....
Bob
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Neat stuff there Marko !!! I wish I had some toys like that to play with, very nice indeed. I need to talk my brother into taking me on another tour through the mold shop he helped a friend of ours put together through the past several years, the last time I seen Paul (mold shop owner) was over at my brothers shooting my SPA M16 soon after I bought it, he really got a charge out of it.
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Good to see someone is back at it...and nice to hear the Emco is up and running too. You've been busy lol.
I like the way you cut that radius. 8) Don't think I've seen it done that way before, but in hindsight it makes a good bit of sense.
Regards,
Al
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Nice bit of machining.... so does the Emco work as a 4-axis mill as well as a lathe?....
Bob
I wish it would, but no it's just a lathe. This was done on the mill with manual dividing head. I have not had the time to setup it as fourth axis and drive it with a servo.
Thanks guys, time is very rare this days. Too much reading and too little machining.
Marko
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Yeah, had to do something like this to the Emco.(http://i11.aijaa.com/m/00684/14546759.jpg) (http://aijaa.com/Dz3WKL)
(http://i9.aijaa.com/m/00019/14546760.jpg) (http://aijaa.com/PhVQKN)
(http://i9.aijaa.com/m/00143/14546761.jpg) (http://aijaa.com/XCeWRA)
And something else that is coming for the mill.
Marko
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Bolt starting to take shape, used and old shock absorber shaft for the material, the hard chrome surface sure is nice.
(https://aijaa.com/img/m/00334/14564451.jpg) (https://aijaa.com/0P4X1V)
Marko
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Erinomaista työtä .......Marko ! ;) Hauska tavata - Tom Wood
( Excellent Work ...Marko ! ;) Pleased to meet you - Tom Wood )
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Kiitos Tom,
(Thanks)
Where did you learn Finnish?
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Kiitos Tom,
(Thanks)
Where did you learn Finnish?
My Computer speaks the Finnish but I live in Minnesota and I am familiar with the way Fins think and act ! There are LOTS of Fin's here. This State was populated in the 1850's by Scandinavians. Finlanders, Danes, Norwegians and Swedes. The French Canadians were already here before the Scandinavians arrived. The Danes, Swedes and Norwegians were mostly farmers while the Finlanders moved to the North with the French Canadians and American Indians doing trapping, hunting and woodworking for a living. There are towns and Villages in Minnesota that are all Finnish, Norwegian, Danish and Swedish. Some still speak the language of their forefathers too. I apprenticed as a Repair Machinist under a Master Repair Machinist that was a Finlander. His Name was Uno Maki. He was the most talented Craftsman that I have ever known. He was Highly Skilled at working with wood or working with metal. He was the person that taught me how to Correctly scrape machine ways, at no-less than 25 bearing points per (6,45cm squared) square inch. My wife is of Danish-Norwegan-French Canadian decent. Her family were amongst the earliest Scandinavians to come to Minnesota. My family was much different. On my fathers side they are Irish and on my mothers side they were Comanche Indian mixed blood. There are two towns, close to where I live, that are Finnish towns, they are named Bruno and Beroun. You would most likely feel at home here. Minnesota looks a lot like Finland. We still have ice on our lakes and some snow in the forests but it will all be gone soon.
My Best Regards & Best Wishes to You Sir - Tom Wood
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Oh my, that sure makes me speechless. A fellow that can scrape machine ways does get my respect! That is a rare talent this days.
It is always nice to find out what people do at the other edge of the world.
Marko
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New atc spindle works just fine, nice to be making parts again using small endmills.
Bolt face has locking lugs machined, more to follow on coming days.
(https://aijaa.com/img/m/00984/14571710.jpg) (https://aijaa.com/yqIjQ6)
Marko
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Main tube coming along slowly, I don't like to machine this stainless tubing. Dulling my endmills and chips are sharp as razor.
But she'll be all shiny and pretty when done.
(http://i1.aijaa.com/m/00188/14571931.jpg) (http://aijaa.com/XBxboL)
(http://i3.aijaa.com/m/00073/14571932.jpg) (http://aijaa.com/5V9T71)
Marko
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And it fits, nice day.
(https://aijaa.com/img/m/00224/14572001.jpg) (https://aijaa.com/Uo6bJu)
Marko
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And a small YT clip of probe turning, if someone should be interested.
https://youtu.be/nt6aCuB2aNA (https://youtu.be/nt6aCuB2aNA)
Marko
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Continuing my monologue, quoting SouthPark. TIMNEYYY, or what ever that wheelchair boy is shouting ;D
(https://aijaa.com/img/m/00468/14572582.jpg) (https://aijaa.com/dQcaxS)
Marko
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Emco seems to be working fine, is the milling machine under computer control?
What kind of trigger unit and any specs?
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Timney sportsman trigger for 98K mauser, cant remember the specs. I usually change the spring for something lighter. It can be adjusted down to hair trigger so to speak.
Mill is an old Victoria U2 universal with all the options it came with. Now running with LinuxCNC.
Just got a new BT30 atc spindle built for it, using it with manual tool change for now.
Marko
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Continuing my monologue, quoting SouthPark. TIMNEYYY, or what ever that wheelchair boy is shouting ;D
Marko
LMBO..It's "Timmy", but we can let it be. ;D
Looks great Marko. 8)
Al
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Thanks Al,
Starting to be close to finishing this build on the mechanical part, couple of more parts for the valve and trigger rear fastener block and end plug for the tube and that's it.
Will be very interesting to test it out on paper.
Marko
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Bolt is about ready, only needs a bolt handle and some anodizing.
(https://aijaa.com/img/m/00834/14572921.jpg) (https://aijaa.com/6qSJzT)
Marko
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Made a little knurling test with single point threading cycle on 12mm titanium. There is some parameter that I need to find, its calculating the speed for threading and sets the lowest rpm possible to 300rpm on 12mm od.
Well feed limit is 2000mm/min on the Emco so I cant get more that 6.5mm pitch on the thread.
Little bit too deep but it's working kind of.
(https://aijaa.com/img/m/00404/14573230.jpg) (https://aijaa.com/JNxLOB)
Marko
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everything lookin good marko.. Interesting idea for the Knurling..forgot to ask , how long is this .223 barrel ?
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Can you set the spindle encoder (or does it have one) as MPG and turn the spindle by hand to get low rpm.
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I'm pretty sure the fanuc / emco gives an error for spindle speed being zero.
I need to go over the parameters, for threading speed it should be in there.
Rob I'll check the barrel length tomorrow cant remember it.
Marko
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I can try guess...Blank was 815mm = 32" but how long is now.. Close orginal I bet it is 31"
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It's 800mm now. So not much wasted length on the bigbulls.
Marko
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Modified the knurling program and ended up with something that resembles katana handle pattern.
I'm going to leave it as is, I kind of like it.
(https://aijaa.com/img/m/00150/14574538.jpg) (https://aijaa.com/EhBrdU)
Marko
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That looks better, almost like some kind of fibonacci sequence on the handle, not too traditional. Vibrating workpiece (when turning) also can provide very nice looking wave patterns.
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That is very true, have seen some amazing prismatic surfaces after vibration on the lathe.
Marko
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That sure look distinctive. Like it also ;D
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Making valve parts is fun with the Emco, cycle time around one minute for first stage. ;D
Balancer frame being turned and threaded.
https://youtu.be/Rnoaz-9_TFE (https://youtu.be/Rnoaz-9_TFE)
Marko
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I'm jealous.... showed the wife and she says "NO, we can't afford it".... :'(
bob
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Those little Emco machines are not so expensive if you keep your eyes open. Have seen the older model go for as low as 800$ on ebay.
The newer are more money of course.
Marko
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Finishing started on some parts, bolt end part anodized.
(https://img.aijaa.com/m/00730/14577321.jpg) (https://aijaa.com/ny2T50)
Marko
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More parts out from the bath.
(https://img.aijaa.com/m/00594/14577698.jpg) (https://aijaa.com/u2B2uL)
(https://img.aijaa.com/m/00353/14577699.jpg) (https://aijaa.com/HUjMm0)
Marko
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what are the small black parts?looks great
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Some misc valve parts.
Marko
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Some misc valve parts.
Marko
;)
They DO look great, getting really good with the anodizing Marko. 8)
Al
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Thanks Al,
I have been keeping records of current and voltage on different parts and alloys.
Now I dont need to calculate surface area to know what should be the current, just check what worked on similar sized part and go with that.
Marko
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Couple of test shots fired with the frame, wood working tomorrow.
Only couple of shots at 200bar, and she has some potential I'm sure.
But its not all good, got tank dump after couple of shot, well turns out that 8mm spring will go over 12mm valve.
67gr 200bar
(https://img.aijaa.com/m/00325/14578024.jpg) (https://aijaa.com/ZJJiZi)
Note to self, stiffer springs.
(https://img.aijaa.com/m/00177/14578025.jpg) (https://aijaa.com/Z8CnrL)
Marko
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931 FPS , nice marko ! that's 128 fpe in 22 cal basically, unbelievable
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Nice job, Marko.... really spitting 'em out at only 2900 psi.... Sounds like that is about the perfect bullet weight for your build (until you push the pressure).... What is the twist rate, and how long a bullet can you get away with?....
Bob
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Thanks guys,
Well if I remember correctly its 7:1 twist so very long bullets will work. But Teemu will know for sure, its his barrel and gun.
Marko
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Be nice to see if something like this would work....
(http://i378.photobucket.com/albums/oo221/rsterne/NOE%20Bobs%20Boattails/224-75-FN_BT__75_gr_Sketch_zpsfz1uibow.jpg) (http://s378.photobucket.com/user/rsterne/media/NOE%20Bobs%20Boattails/224-75-FN_BT__75_gr_Sketch_zpsfz1uibow.jpg.html)
Theory says a 7" twist should be OK....
Bob
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Yeah it is 7" I have have couple long desing. One is MP Molds 75 gr FT and other is NOE's 80 Sprire Point. Same bullet is on my avatar. I think Spire is .907 long...Need to measure for sure
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My 75 gr. BBT is 0.896" long (4 calibers)....
Bob
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Which diameter is that your bullet Bob? .224?
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Wood dust day...
(https://img.aijaa.com/m/00347/14578481.jpg) (https://aijaa.com/QaiiPR)
(https://img.aijaa.com/m/00905/14578482.jpg) (https://aijaa.com/03IGFL)
(https://img.aijaa.com/m/00980/14578505.jpg) (https://aijaa.com/geBDqJ)
Marko
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Outstanding!
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Yep, designed at 0.224", with a narrow 0.226" driving band.... easy to size though....
http://noebulletmolds.com/smf/index.php/topic,1128.0.html (http://noebulletmolds.com/smf/index.php/topic,1128.0.html)
The center portion is 0.216" to clear the rifling to reduce drag....
Bob
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Tanks Terry,
It has been a long build and now if's finally close to being finished. Started this the same time I started the previous.223 project.
This one how ever has the features I would want in a rifle. Balanced valve for easy cocking, removable bolt without tools for easy cleaning. Multi caliber capability without removing the upper from the lower.
Marko
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First teaser of the complete rifle.
More pictures will follow when the owner has seen the rifle. ;)
(https://img.aijaa.com/m/00446/14579776.jpg) (https://aijaa.com/LgpDhP)
Marko
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incredible, love the breech design
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Thanks Rob,
It's much like pb breech, locking lugs in the front and removable bolt.
Marko
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Pretty impressive build Marko. Can’t wait to see all the details / more pics.
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Ou man...Didin't get much sleep last night...Wonder why? :o
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Thinking about the name I gave your rifle? ;D
Marko
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So lucky shot got his rifle today, we have been testing it out on the range.
Best power seems to be around 280bar, 57gr goes at a whooping 338m/s 8)
I swapped another valve in today and that will stay on the rifle.
Most astonishing that same bullet did 292m/s at 180bar. Valve and porting seems to be about perfect.
We have lot of labradar data to check this evening.
(https://img.aijaa.com/m/00572/14580072.jpg) (https://aijaa.com/3EpTBy)
(https://img.aijaa.com/m/00816/14580073.jpg) (https://aijaa.com/PNBFH1)
(https://img.aijaa.com/m/00550/14580074.jpg) (https://aijaa.com/NkXyS6)
More testing tomorrow.
Marko
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Probably running out of barrel at 280 bar, you need a heavier bullet to drop the velocity and gain FPE.... Nice job, guys !!!
Bob
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Nope Bob, its working the same with just about every weight projectile.
Runing around 200J +- 15J with different bullets on 280bar.
Groups average 20-50mm to 100 meters in windy conditions, Teemu shot days best 5 shot group about 10mm.
(https://img.aijaa.com/m/00371/14580780.jpg) (https://aijaa.com/KOzDH1)
Marko
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excellent groups Marko !
I think what Bob means , and I could be wrong , is that the pressure ( 280 bar) would have the lighter pellets continue to accelerate in a longer barrel .. ( in theory , theyd keep picking up speed even in a 4 foot barrel ) Whereas the heavier slugs may not.. So in this length barrel , the fpe numbers would peak faster with heavier slugs.
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Not really.... With the lighter bullets, you are pushing supersonic, and the internal efficiency takes a dump when you do that.... It takes a lot more air, or a lot longer barrel, to make gains.... If the velocity is under 1000 fps, changes in pressure or barrel length make a bigger difference.... If you are reaching over 1100 fps (335 m/s) it's time for a
lighter heavier :-[ bullet, IMO.... I look for a heavier bullet once I am over 1000 fps.... as the wind drift is increasing quite noticeably at those speeds (about 50% more drift at 1100 than at 900 at 200 yards).... The combination of having to use a lot more air to go faster, and increased wind drift are simply not worth it, IMO....
However, you sure can't beat a group like that at 100 M.... :o 8)
Bob
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I think you meant to say heavier bullets...
anyway that group was shot at around 331m/s, its not always just under supersonic when something works, have seen best groups over 340m/s on some gun / bullet combo.
One more range day tomorrow, today was a good day despite the wind, hitting 10" steel target at 300m with the 20mm using sabots and .516 spitzers. I belive Teemu got that on video also
Same POI at 100m using 120gram bullet as 300m with sabot rounds. Its very consistent to shoot with sabots.
Marko
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Here is LabRadar data for 57 grainer from one shot. Unbeliavable how far it measures those small bullets. Red line is trend curve as there comes increasing noise in the end part. I think it fits well enough to show close to real velocity. At least my LabRadar has always measured longer distance than it was stated to be capable.
(https://img.aijaa.com/b/00389/14581688.jpg)
X-axis is meters of course.
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Just looking at that data, I would throw out anything past about 147 M as you start getting really big spikes in the velocity.... You could even make the same argument for stopping at about 112 M I guess.... Even at that distance, it is wayyyyyyyyyy beyond what LabRadar claim to be the effective range, particularly on a .223 cal bullet.... The data out to about 70 M is rock solid, however.... Taking a distance interval of 60 M (from 10 to 70) and using the red trend line, I get a BC (G1) of about 0.42.... assuming your testing was done at sea level on a "normal" day.... Pretty staggering BC, what does the bullet look like?.... Incidently, I get the same BC between 10 and 145 M....
Bob
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(https://img.aijaa.com/m/00839/14582082.jpg) (https://aijaa.com/Xr6NJa)
First on right side
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Weather conditions were; 20C, 1011hPa, 50%RH, elevation 116m. Weather is checked from nearest Finnish Meteorological Institute weather station data in the time of shooting. It is located about 30km from range.
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And I agree the rest part of LabRadar data is pretty much useless but just somehow "incidentally" trend line will always give the same BC... Maybe it just is what trend line is for.
We also tested with heavier bullets of course and naturally speed with them is lower but calculated energy was quite accurately the same. Only some 5% difference recardless the weight.
What comes to efficiency I must say we are not that much interested of it because hunting with airguns is not allowed here and we have a compressor and booster on range every time. What we are interested of is only consistency and accuracy. And power of course. Our situation is we have enough air for almost anything, interest in development and a lot of fun as a side effect. There are apples and oranges yet both are fruits.
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Yes, the trendline can be a great tool.... but a linear trendline for a bullet (which looks like what you used?) shouldn't be correct when you are starting near Mach 1.... The bullet is slowing down more at the beginning, you can see that on your chart, it is above the trendline from the muzzle to about 30 M, then slightly below, the appears to be above again from 90-100 M.... If you threw out the data over 112M (which would increase the resolution of the graph) and redid the trendline using a Polynomial you should start to see that curve.... Then use that to calculate the BC.... If you only used the data out to 70M the curve would be even more pronounced.... Just a suggestion....
Bob
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Ok, data is not a secrecy but how can I share it? Suggestions?
Silly me, stupid question, sent.
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Timo sent me the raw data, and discarding the readings past 112 M, using a Polynomical Trendline, and correcting for his atmospheric conditions, I got a BC (G1) of 0.365 for the 57 gr. bullet.... pretty fantastic....
Bob
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I still think it is not true. That is about the same BC I got but when I compare it to resulted scope elevation from several ballistic calculators it doesn't fit at all.
For this bullet I don't have a match but speaking of my .452 XP I have calculated BC 0.268 from Labradar velocity data. Real one which appears to be right on trajectory calculator is 0.171. With that interpolated BC it gives me perfect corrections for every distance. Measured and calculated by velocities seems much too high.
I could have use for explanation of this if anyone have.
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Unless the LabRadar data is wrong.... I have no other logical explanation.... :-\
Yes, 0.365 does seem way too high, that indicates a Form Factor of 0.45, which is pretty much unheard of.... ::)
Not many FB bullets have a FF lower than 1.0, which with the SD of 0.164 would give a BC of the same.... If that is the NOE 57 gr., they give the calculated BC at 0.200, but no velocity stated of course....
Bob
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I think the data is wrong. We have tested it against chrono and velocity is correct but that long distance just can't be. I'll check that when possible.
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Weird thing is that if you take the time of flight to 111.78 M it is 0.347 sec, which works out to an average of 322 m/s.... That is pretty much exactly on the trendline.... If the distances were wrong (ie shorter than the data string), then the average velocity to any given distance would not agree with the trendline average....
I have no idea what the problem is, but like you, I don't believe the data....
Bob
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I checked that too and all the distance, speed and flight time values match together which is pretty weird. What I can think maybe there is slightly wrong clock frequency. Time would be incorrect and if it calculates distance from time all seems to match. Speed comes from doppler shift so it can be right at close range. But without knowing how it really works in details this is only quessing.
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If the clock rate is wrong, the near velocity should be wrong as well.... IMO.... I'm at a total loss, but I would use a conventional Chrony, and check it at 5 yards and 70 yards and see what you get....
Bob
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Maybe reading in yards and your thinking in meters? setting issue? Just making guesses because it is something I would probably do. then beat myself up for a week :-[
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Truly amazing craftsmanship! ;)
Do you have some info/pics to share about the balanced valve you made?
Also do you use a probe or do you seat the bullets by hand?
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Thanks Jim,
Well the valve is something I wont share in open forum, but you can get similar designs from cothran.
I use retractable probe on this build and it will be utilized on future builds as well.
Marko
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Thanks Jim,
Well the valve is something I wont share in open forum, but you can get similar designs from cothran.
I use retractable probe on this build and it will be utilized on future builds as well.
Marko
Thanks!
How does the retractable probe work? I quess it is not a J-slot type or is it?
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You can see it in the last picture I posted. Bolt is in the locked position and there is a slot in front of it. You just seat the bullet and retract the bolt, lock it down.
Marko