GTA
All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Topic started by: cosmic on March 09, 2019, 11:55:11 AM
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Just wondering what barrel would be good for a .177 15.5 gr slug shooter in the 925 fps range would be.. Let me know..
Thanks..
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I was trying to get hold of a Chinese company to make a .22 bullet barrel (arrowy flier) they say that they do blanks to custom parameters, but I could not get hold of them.
They do make unchoked blanks in .177 with a twist rate of 1 in 17" 10-28" long and you could maybe ask them to make a blank in the twist and length that you need for you bullet.
If some one made bullet barrels in the common airgun cailbers .177 .22 .25 I would certainly assume there was a market for it!
But only .25 is available as bullet barrel what I know of and it is not really a airgun caliber (.25acp).
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I think most guys doing a .17 slug shooter are doing the .172 in a 1:9 twist TJ's barrel.
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Here's some prices.
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Not a hope of a 17" twist working for bullets in .177 cal, you need the additional drag stabilization of a Diabolo pellet to get that slow a twist to work in that caliber, IMO.... Depending on the actual bullet dimensions, you might get something in the 12" twist range to work.... The 9" twist TJs barrel is perfect for the 24-26 gr. NOE bullets.... http://noebulletmolds.com/NV/index.php?cPath=102 (http://noebulletmolds.com/NV/index.php?cPath=102)
Contact Nick at NSA.... He is developing bullets for .17 cal airguns, and should be able to tell you what barrels they will work in....
Bob
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Ray,
I ordered some custom 1:10" twist .177 polygonal barrels from Lothar Walther last year. I haven't had the time to do anything with them yet. My intent was to try to get a decent H&N Piledriver shooter. If that didn't work out then try NSA bullets.
I also bought a mini lathe last year but I am hesitant to cut my teeth on expensive LW barrels. lol
I think I will visit a machine shop and see if they will be willing to machine the barrels for me. I'm going to start with Weihrauch HW100 and BSA Scorpion SE pattern and see how they work.
Thanks,
Taso
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So far the LW poly unchoked is all I have found..
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Ray,
Mine were special order. It took like 4 - 5 months to get them and there was a minimum of 5 barrels.
Thanks,
Taso
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Definitely can not afford that !!
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My Mrod barrel is 1:17, it will shoots 21gr NSA really good at 50 yards, (850fps) I think I need to get the fps up in the 925-950 fps to get better accuracy. I will be working on it again very soon. Just working too much right now. 100 yards it opened up to 2 3/16" of an inch on a bad day for shooting in a canyon justing from all directions. I want to see what it does again on the next outing before messing with the barrel.
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Huh, well looky there.... *LOL*…. So much for theory.... Kolbe Twist Calculator says 14" twist optimum for that bullet at 900 fps....
Yep, Nick knows what he's doing, all right.... 8)
Bob
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Yea, that's a 5 shot group too at 50 yards. I cannot wait to see what the barrel can do with a few more fps and maybe some lapping if needed.
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Your accuracy could well be worse at 900-950 fps, than at 850.... That's just what happens in the Subsonic region.... the greatest chance for a bullet to tumble occurs at around 1100 fps.... Here is the Kolbe graph for your 17" barrel with that bullet....
(http://i378.photobucket.com/albums/oo221/rsterne/Ballistics/122503_zpsbixtnust.png) (http://s378.photobucket.com/user/rsterne/media/Ballistics/122503_zpsbixtnust.png.html)
Note that it drops into the unstable zone (SF<1.0) at about 950 fps.... :o
Bob
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2004 on Daisy 953 barrel is 19" long... 1:15 twist and when I ordered one a few years ago they were $40... but like other pellet barrels not a lot of rifling height...
So if they are of a soft steel might wear out quickly...
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Your accuracy could well be worse at 900-950 fps, than at 850.... That's just what happens in the Subsonic region.... the greatest chance for a bullet to tumble occurs at around 1100 fps.... Here is the Kolbe graph for your 17" barrel with that bullet....
(http://www.geoffrey-kolbe.com/images/952174.png)
Note that it drops into the unstable zone (SF<1.0) at about 950 fps.... :o
Bob
Bob, thx for the info.
I will give it a go and see at what fps the slug likes and run with the best accuracy over fps any day.
I sure want to put the smackdown a Jack rabbit really bad.. My t-finger has gotten da itch to be squeezing, I cannot lie.
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Ray,
I ordered some custom 1:10" twist .177 polygonal barrels from Lothar Walther last year. I haven't had the time to do anything with them yet. My intent was to try to get a decent H&N Piledriver shooter. If that didn't work out then try NSA bullets.
I also bought a mini lathe last year but I am hesitant to cut my teeth on expensive LW barrels. lol
I think I will visit a machine shop and see if they will be willing to machine the barrels for me. I'm going to start with Weihrauch HW100 and BSA Scorpion SE pattern and see how they work.
Thanks,
Taso
Taso,
I am awaiting on yours results patiently/impatiently. :'(
Peter
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Ray,
I ordered some custom 1:10" twist .177 polygonal barrels from Lothar Walther last year. I haven't had the time to do anything with them yet. My intent was to try to get a decent H&N Piledriver shooter. If that didn't work out then try NSA bullets.
I also bought a mini lathe last year but I am hesitant to cut my teeth on expensive LW barrels. lol
I think I will visit a machine shop and see if they will be willing to machine the barrels for me. I'm going to start with Weihrauch HW100 and BSA Scorpion SE pattern and see how they work.
Thanks,
Taso
Taso,
I am awaiting on yours results patiently/impatiently. :'(
Peter
Aren't we all,lol!
Just wondering what barrel would be good for a .177 15.5 gr slug shooter in the 925 fps range would be.. Let me know..
Thanks..
I've gotten good results out of my choked polygon with the 21 grain NSA slugs shooting around 925fps. I haven't tested it past 45 yards though. I will say, I can't get the 15.5 grain to shoot well out of it for nothing though :(
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Hey All!
I have an update. I finally had a chance today to stop by three machine shops.
The first shop wouldn't touch it because it was related to guns. I reiterated it was an airgun. He said no.
The second shop was too busy to take on my little job.
The third shop looked at what I had and said he would get back to me. I brought him the LW blank, the HW100 barrel I wanted him to copy, the HW100 receiver to see how the barrel mates and a tin of Piledrivers and a bag of NSA 18 grain bullets. I asked him if it was possible to cut a 1° tapered leade. ( I got that idea from one of Bob Sterne's posts. ;) ) He said he has to see if he can find a reamer. I didn't have much confidence in him because it seemed he didn't know what I was talking about. He took down my number and said he would get back to me.
At this point I'd rather ship my barrels off to someone who's done this before and knows the in's and out's.
Do any of you have any recommendations on who to contract for this?
I've also been in contact with the maker of the Heliboard. I am going to order his extreme board for my Daystate MK4i. I think it will be a great test bed because of the easily switchable velocities to see which will produce the best accuracy with the different pellets I test through the 1 in 10" twist rate.
So that's two different barrel types I need made.
So that's where I'm at. I apologize for it taking this long. I am very eager to see how this will work out.
Thank you!
Taso
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Talk to Matt at JSAR. If you send your barrel and receiver in im sure he can't get it machined up for you. He did a barrel for me before.
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Hey All!
I have an update. I finally had a chance today to stop by three machine shops.
The first shop wouldn't touch it because it was related to guns. I reiterated it was an airgun. He said no.
The second shop was too busy to take on my little job.
The third shop looked at what I had and said he would get back to me. I brought him the LW blank, the HW100 barrel I wanted him to copy, the HW100 receiver to see how the barrel mates and a tin of Piledrivers and a bag of NSA 18 grain bullets. I asked him if it was possible to cut a 1° tapered leade. ( I got that idea from one of Bob Sterne's posts. ;) ) He said he has to see if he can find a reamer. I didn't have much confidence in him because it seemed he didn't know what I was talking about. He took down my number and said he would get back to me.
At this point I'd rather ship my barrels off to someone who's done this before and knows the in's and out's.
Do any of you have any recommendations on who to contract for this?
I've also been in contact with the maker of the Heliboard. I am going to order his extreme board for my Daystate MK4i. I think it will be a great test bed because of the easily switchable velocities to see which will produce the best accuracy with the different pellets I test through the 1 in 10" twist rate.
So that's two different barrel types I need made.
So that's where I'm at. I apologize for it taking this long. I am very eager to see how this will work out.
Thank you!
Taso
Matt at JSAR is phenomenal at any barrel you want machined. Everyone of my rifles are highly customized and Matt has made me some amazing parts. Very easy to deal with and the prices are very fair.
Peter
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Another small update:
Today I shipped two barrel blanks and an HW100 and Daystate MK4 barrel to copy to Matt at JSAR. I think he said it should take around a month or so to complete.
I apologize for the delay. I got swamped with work and had to focus on many projects.
I still have to find property to setup a 100 yard range.
I thought about putting an add in a local paper or maybe Craigslist. Has anyone done this before? Any tips?
Thank you,
Taso
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Interested to see how it does for you.
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Chris,
Me too! When I ordered the custom twist rate barrels I was taking a gamble that the Kolbe twist calculator was correct with it's estimate for Piledriver pellets.
But then Tofazfou made his HMAir build using a TJ's liner in .172" with 1:9 twist and it's working very well for him. That was a great confidence boost that my gamble would pay off.
I am almost there. ;D
Thank you,
Taso
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UPDATE!!!
I just got off the phone with Matt at JSAR. My barrels are done! :D
I paid for the machining and they will be shipping back to me today.
That I am excited is an understatement!
Taso
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That's great, I can't wait to hear how they do!
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I second that!
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Any good results on your .17 barrels??
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Odd how many go completely quiet in the middle of a project that they have gotten people excited over. It happens over and over again. GRRRRRR!!!!!!
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Life sometimes throws you a curveball every once in a while and you have to deal with the life matters over bb-guns.
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True that!
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I shoot a marauder in 177 shooting the nsa 15.5 slugs at 830 FPS, it holds one inch groups at 100 yds.
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I shoot a marauder in 177 shooting the nsa 15.5 slugs at 830 FPS, it holds one inch groups at 100 yds.
Are you using a stock Mrod barrel, and what is the twist on it?
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To the orgihnal question (post #1)....if they are the 15.5gr. slugs I'm thinking about,they should work in a standard twist factory barrel...although you'll get arguments against choked barrels.
That company (Neilson?)swages pellets and includes the length in the description...and I've gotten regular pellets ofd about that weight and greater length to shoot well in most .177's...so it wouldn't be a barrel twist issue...could just be the obstinate nature of airguns to only like certain pellets,but you shouldn't see oval holes or key holes.
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Hey All!
Sorry for the lack of recent updates. I did get one of the barrels mounted in what was a .22 Daystate Airwolf. I also installed a Heliboard Extreme and on the highest power (12) it's pushing Piledrivers at 1005 fps at the muzzle.
Accuracy at 13 yards is not one .177" diameter hole as I'd wished.
I have read that the projectiles need some distance to stabilize so I think 13 yards may not be enough.
I still haven't found 100 yards to setup targets to test and tweak. So I really can't say if the twist will work.
One thing that I have noticed is that the Piledrivers have very little engraving from the polygonal rifling. Is it possible the barrel dimensions are larger than the standard .177"? I'll attach a couple pictures that I fired at power setting one into bubble mailer envelopes. I'll shoot a NSA 21 grain bullet and attach pictures of that as well. I'm getting some large extreme spreads so I think the Piledrivers may not be sealing the bore and allowing blowby. Just guessing.
In the interim I have been messing around with barrel weights to increase accuracy. I started at the end of the barrel and have gradually come back about .25" with no accuracy increase. This could take forever lol.
Does anyone know how to calculate the theoretical distance from the muzzle that I should start at?
Thanks,
Taso
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Those NSA markings are very similar to those of my standard twist poly barrel(as in how much of the slugs are in contact with the barrel). The Piledrivers tend to be undersized I think. I've not measured any, but I've read many accounts of them fitting loosely in barrels, fwiw.
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Those NSA markings are very similar to those of my standard twist poly barrel(as in how much of the slugs are in contact with the barrel). The Piledrivers tend to be undersized I think. I've not measured any, but I've read many accounts of them fitting loosely in barrels, fwiw.
Hmmmmm... Now I'm curious to what they look like at max power and if they deform to seal in the barrel? I'll be right back! ;D
Taso
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I've gotten regular pellets of about that weight and greater length to shoot well in most .177's...so it wouldn't be a barrel twist issue.
Regular pellet will fly nose forward out of a smooth bore due to drag stabilization. Conical slugs are tail heavy and rely fully on spin stabilization. So, I am not sure that long heavy pellets tell us much about slugs, except perhaps for some indication of velocity.
Trying short slugs in a standard barrel certainly seems like a reasonable idea. If the choke is a problem, the barrel can be cut off...
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I couldn't get the 15.5 to shoot well out of my standard twist poly barrel for anything. I didn't get to do much testing of the 18 grain. I was able to get good results with the 21 grain, but only above 915-930fps. I have choked poly barrel, but the choke has been highly polished, so very little choke.
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Taso, to bad you didn't live closer.. Willow Slough in Indiana has a nice range and 100 yards.. And I have a 100 yard range across the street that a neighbor let me cut in a overgrown paintball field.. I used to live in Frankfort..
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Taso, to bad you didn't live closer.. Willow Slough in Indiana has a nice range and 100 yards.. And I have a 100 yard range across the street that a neighbor let me cut in a overgrown paintball field.. I used to live in Frankfort..
Ray,
In the early 90's I used to drive to Hoopeston to deliver supplies to my uncle's restaurant. It was a haul. :(
Taso
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So trying to capture projectiles at full power was useless. On my first attempt they went through all the material I tried to capture them with and smashed into the concrete floor and embedded themselves under the carpet. Ooops!
I next tried capturing them in a book. That just demolished them instead. That's what the first picture is. They are Piledriver, 21 grain NSA, 13.43 grain JSB and Crosman Premier Heavy.
The rest of the pictures were taken a power level 3. Same pellets/bullets as before.
Thanks,
Taso
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Hi Taso,
My question in bold below the image, is based on the assumption that your custom twist poly barrel has the same bore and groove diameters as the regular LW poly barrel. Also, that your custom barrel uses LW's typical rounded poly land, rather than "ratchet style". If none of my assumptions are correct, then the info and logic below are academic:
I re-looked at your images after I wrote this message; then snagged the fired slug image directly below:
Slanted rifling engagement mark suggest this is ratchet style rifling:
(or that the slug skidded a little)
(https://www.gatewaytoairguns.org/GTA/index.php?action=dlattach;topic=155749.0;attach=289450;image)
I hate to ask this question, after the fact;
but why choose a poly barrel for slugs?
Especially, since the rifling engagement is not full depth.
Using the LW bore and groove diameters from the links below, and NSA's statement that their slugs are .177" diameter, I modeled the rifling to slug engagement for both the 12 land and regular (not ratchet) poly barrels. See images below.
Note how there is no "shoulder" on the poly land to slug engagement. Now, if the slugs shoot well at full power, and there is no skidding on the lands, then my rifling choice question is of even more dubious value. If there is excessive skidding, then perhaps a .178 or .179" slug might improve that.
I recognize that there is some aliasing in the models, that distort the images slightly (magnified circles are not perfectly round, but have facets). This is an artifact of SolidWorks display resolution:
Side by side; LW 12 land VS poly barrels in .177 caliber; with NSA slug in bore:
(https://www.gatewaytoairguns.org/GTA/index.php?action=dlattach;topic=155749.0;attach=289438;image)
Maximum interference between conventional LW land and NSA slug = 20 micron = .0008"
(https://www.gatewaytoairguns.org/GTA/index.php?action=dlattach;topic=155749.0;attach=289440;image)
Maximum interference between poly LW land and NSA slug = 20 micron = .0008":
(https://www.gatewaytoairguns.org/GTA/index.php?action=dlattach;topic=155749.0;attach=289442;image)
Regular LW barrel has a .0008" high "shoulder" near perpendicular at land to slug engagement:
Please ignore the faceted look of the model when "zoomed in"
(https://www.gatewaytoairguns.org/GTA/index.php?action=dlattach;topic=155749.0;attach=289444;image)
Poly LW barrel has no "shoulder" near perpendicular at land to slug engagement. Angle is very shallow:
(https://www.gatewaytoairguns.org/GTA/index.php?action=dlattach;topic=155749.0;attach=289446;image)
This article shows regular pellets fired from polygonal rifled airgun barrel have higher velocity and higher BC, compared to regular rifling: https://airgunaccuracy.wordpress.com/polygonal-and-rifled-barrels-compared-for-bc-and-velocity/. (https://airgunaccuracy.wordpress.com/polygonal-and-rifled-barrels-compared-for-bc-and-velocity/.) How this correlates to firing slugs is what I would like to know
(https://airgunaccuracy.files.wordpress.com/2015/09/polygonal-barrel.jpg)
(https://airgunaccuracy.files.wordpress.com/2015/09/2-visier-test-diabolo-pellets-and-rifled-and-polygonal-barrel-profiles-compared.jpg)
LW barrel dimensions:
https://www.lothar-walther.de/barrel-blank/airgun/standard-profile-with-choke/1458/airgun-blank-choked-4-5mm-air-od-9-mm-l-605-mm?c=273 (https://www.lothar-walther.de/barrel-blank/airgun/standard-profile-with-choke/1458/airgun-blank-choked-4-5mm-air-od-9-mm-l-605-mm?c=273)
https://www.lothar-walther.de/barrel-blank/airgun/polygon-profile-with-choke/1472/airgun-blank-choked-4-5mm-air-polygon-od-10-mm-l-605-mm?c=273 (https://www.lothar-walther.de/barrel-blank/airgun/polygon-profile-with-choke/1472/airgun-blank-choked-4-5mm-air-polygon-od-10-mm-l-605-mm?c=273)
NSA slug dimensions:
https://nielsenspecialtyammo.com/collections/177-caliber/products/15-5-grain-hollow-point-air-rifle-pellets-177-caliber-air-gun-slug-swaged (https://nielsenspecialtyammo.com/collections/177-caliber/products/15-5-grain-hollow-point-air-rifle-pellets-177-caliber-air-gun-slug-swaged)
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Hi Subscriber,
I picked polygonal rifling because I had read that the the 6 smoother marks the polygonal rifling makes on projectiles are more aerodynamic than the 12 sharper grooves that the lands cut into the projectile in standard rifling.
I also thought the polygonal rifling should provide a better seal between the barrel and bullet. I used the Kolbe Twist calculator that Mr. Sterne had linked to in one of his posts. I modeled the Piledriver bullet and picked the 1 in 10 inch twist. I never considered pellet use.
Here is the thread I created in my quest for a .177 slug shooter: https://www.gatewaytoairguns.org/GTA/index.php?topic=145128.0 (https://www.gatewaytoairguns.org/GTA/index.php?topic=145128.0)
I have attached the barrel spec's that the LW salesperson gave me. The only difference with my custom ordered barrels was the twist rate.
Thanks,
Taso
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Thanks Taso,
Logical reasons for your choice.
What I am not sure of is if LW poly barrels have symmetrical rounded lands, but that is what I took from images I found. I certainly understand why these rounded lands would be aerodynamically appealing when imprinted into the slug.
In any event, the land imprints in the slug you pushed through the barrel (image from your link above) look shallower and more rounded than the fired one (unless I am seeing what I want to see :) ). Both images pasted into this post, below.
This suggest my SW model is correct with rounded lands, and that your slugs may be skidding a little when being fired.
Now, if you looked through the barrel you would be able to tell immediately.
What matters ultimately is if your system shoots well. Consider the rest, academic heckling :)
Pushed through barrel:
(https://www.gatewaytoairguns.org/GTA/index.php?action=dlattach;topic=145128.0;attach=281027;image)
Fired through barrel at low power:
(https://www.gatewaytoairguns.org/GTA/index.php?action=dlattach;topic=155749.0;attach=289450;image)
(https://3.bp.blogspot.com/-aeZrBimWfmo/UYF5GftyK0I/AAAAAAAAFe0/ZtxtFkanfSY/s320/HGR_Barrels_and_Rifling_Profile_Types.jpg)
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Subscriber,
I have attached the best picture I could take of the rifling shape. The lands look flat to me.
As for the asymmetrical shape of the land impression on the NSA slug, I don't know. Maybe it didn't go into the leade perfectly concentric to the bore initially and then straightened out as the rear portion straintened it's orientation to more concentric? Maybe the leade needs to have a smoother transition?
Three of the indentations from the grooves look symmetrical. There is another one that matches the one in the picture you pointed out. and the sixth has the slant in the opposite direction.
Thank you,
Taso
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Thanks Taso,
I think the lands have a 122 mm radius to them, that looks flat compared to the groove diameter. See image from my model below (dimension in green).
I agree that if the slug skidded rotationally, all six lands would be affected equally. That the artifact I identified could be explained as yawing during loading, as you suggested. Don't know what your chamber and loading system look like.
(https://www.gatewaytoairguns.org/GTA/index.php?action=dlattach;topic=155749.0;attach=289467;image)
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Interesting that the .177 conventional rifling LW barrels are 0.176" x 0.182".... but the polygonal rifling barrels are 0.175" x 0.181".... If Nick's slugs are sized 0.177", it is not much wonder they barely touch the lands, the barrels are obviously sized for pellets.... I would assume that if the barrel was choked, you would see deeper rifling marks.... What is the diameter of the Piledriver before shooting it?....
Bob
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I think the angled grooves might just be the lead. I just pushed a 15.5 NSA slug through my .177 Hatsan Flash barrel and it has very clean, crisp grooves, but they are angled on top too.
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To answer the question asked on the barrel yes it is just a standard Crosman barrel.
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Correction to my previous message. I grabbed a magnifying glass, and the grooves on the NSA slug are even, but pointed at the top. kinda odd. I'll post a pic in the morning.
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Wow - project is continuing.
I haven`t own yet faster TR barrels but In according of my experiences :
1. Slug barrels can not be choked
2. Small engraved channels on slugs with much less/smaller volume/content of air and therefore smaller air turbulenece are better.
3. Wiehrauch barrels are engraving much smaller/narrov channels on slugs and pellets and they seems to be best for slugs
If I am right Wiehrauch barrels are also produicing at LW factory.
Is it possible to order it too with faster/custum TRs at LW factory ?
Bob,
They was/are? two types of .177 Piledrivers
1. body size 4,46mm
2. body size 4,5mm
Head size is about 4,53 mm
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i thought that weihrauch produces their barrels in their own factory.
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i thought that weihrauch produces their barrels in their own factory.
Unless something has changed, you would be correct:
https://www.youtube.com/watch?v=VgCQf16QSjk (https://www.youtube.com/watch?v=VgCQf16QSjk)
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Wow - project is continuing.
I haven`t own yet faster TR barrels but In according of my experiences :
1. Slug barrels can not be choked Sorry Peter but that is just not true... has been done for a long time in .22lr... I personally have a 1950's choked Beretta .22lr barrel(Very close relation to the SuperSport rifle)... and has been done by me and others here with with PCPs with varying success...there are issues to be sure but most of the time solutions can be found...
2. Small engraved channels on slugs with much less/smaller volume/content of air and therefore smaller air turbulenece are better.
Well yes for the most part that is my philosophy also but matters most at more extreme ranges... closer range not as much... it has been around since before Harry Pope was making Barrels...
But it is the base of the round that is most important it is what steers the round the most... A short rebated boat tail goes a long way into mitigating that problem... IMO...
3. Wiehrauch barrels are engraving much smaller/narrov channels on slugs and pellets and they seems to be best for slugs...
If I am right Wiehrauch barrels are also produicing at LW factory.
Is it possible to order it too with faster/custum TRs at LW factory ?
Bob,
They was/are? two types of .177 Piledrivers
1. body size 4,46mm
2. body size 4,5mm
Head size is about 4,53 mm
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Thank for repairing/improving my post. Maybe tail of 21gr Piledrivers act also as boat tail ?
Notice:
Increasing velocity from 880FPS to 935FPS have improved accuracy a little bit at Wiehrauch barrel which can be also way for Polygonal barrels or faster/custom TR poly barrels.
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I would think that the Piledrivers would very much act as a boattail…. and as such need a bit faster twist rate than if they had a flat base.... Taso took all that into consideration before he ordered his 10" twist unchoked LW poly barrels....
Bob
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Been following along....and I understand the concept of a really high BC slug (reguardless of the energy) in windage down range.
figure there were two ways to go about it:
1. Fit a new fast twist barrel for a really long shapely .172"slug.
2.Make the best shapley slug for the length that would work in a standard .177 barrel.
Piledrivers don't seem to be "it" for #2.
HAve posted this before....but I really tried to like Piledrivers and standard factory barrels.
Test 14 different rifles (some were borrowed), and did find one that was useful(a cut to carbine length QB barrel) and one that was "eh".
Pretty much gave up at that point (pretty well testshooting 3 of the 4 tins ordered) and shot up the last of the Piledrivers in the one standard barrel that actually tolerated them (about 1" at 50 yards for a long term average).
WHY did the one barrellike them? Likely will never know. Tested fast guns,slow guns,choked barrels, no-choked barrels, thin probes,fat probes,hollow bolt probes,and no probe at all (Air Force).
Am just going to think of that one odd-ball barrel as "the exception that prooves the rule" and move on...won't be ordering anymore unless I come up with a faster twist barrel.
Even that one standard twist barrel that did shoot them well enough to use "went stupid" much past 50 yards.
Under 50 yards,they flew straight and made round holes...but if shot into anything (ballistic tyoe gel or a critter) then lost it and tumbled internally. That was great for little critters...but why would I want 21gr. .177 for little critters under 50 yards?
Mine were clean and uniform, but they may have gotten worst (which happens to lower volume selling pellets....they keep the forming dies in use longer and likely let the QC slip a little).
Salute "them"for the effort...was worth the try on their part (or at least the orginators of the Pilediver in the UK).....it just might have been better just a little shorter and a little lighter (lets say 17grains) to be liked by more standard twist barrels.
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...it just might have been better just a little shorter and a little lighter (lets say 17grains) to be liked by more standard twist barrels.
I agree . BC do not need to be 0,082
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Soooooo, the final results for best projectile/barrel combination in .177 is.....
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SSSSSHHHHH, it's a secret lol.