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charger 1
04-01-2009, 01:07 PM
I'm noticing my guns that are all 458 cal,using the same PP boolit seem to be more accurate if their a faster twist. ie my lott is more accurate than my 45/70. Both rugers. Is this because the faster spinning blows the paper off better?

pdawg_shooter
04-01-2009, 01:38 PM
Dont think so. I have a .458 with a 1 in 22 barrel and one with a 1 in 14 barrel and the slow twist is more accurate WITH A 430gr BULLET. Try some different length bullets and see what happens. Could be just the difference in the barrels, the paper, the seating, or just the way you wrap them.

windrider919
04-04-2009, 10:19 PM
I shoot .458 Win Mag with an 18" twist barrel that has average accuracy with J-bullets (2 1/3" @ 100) with the best bullets in the 350gr range. However, using PP and a 460gr bullet I get 1" or less. The 500 + bullets do not have as good of accuracy with my very best group being being 1 1/2". I must note that my 460gr bullets are .454 + .008 PP which works for smokeless but not BP.

montana_charlie
04-05-2009, 11:49 AM
more accurate if their a faster twist.

Is this because the faster spinning blows the paper off better?
I seriously doubt it.
You know how important a perfect muzzle crown is...right? The smallest defect can kick the bullet off line enough to open a group.

Paper clinging to a bullet - even for just a turn or two - would have to be equally detrimental.

The paper needs to be sluffing away right at the muzzle because it has been properly shredded...not getting flung of by rotation after it has exited.
CM

windrider919
04-05-2009, 12:32 PM
In the debate all I can say is that it would take a high speed camera taking pictures of various PP bullets AND different rifling styles / depths. My 18" twist with 6 rifling grooves are comparatively wide with the lands being half as wide. Looking down the barrel they barely stick up. Its hard to believe they are .004 A friends barrel has 4 lands and grooves and his grooves 'appear' deeper, almost twice as much as mine yet his is a .458 cal too (14" twist). He occasionally gets long strips of paper recovered in front of the muzzle. I never get anything but confetti so small that it is hard to see. He frequently can find the base 'twist' yet I again, never have. I have identified a fragment of a corner of the base paper a couple times. Obviously, something different is happening between our two rifles, shooting the same PP bullet, just loaded into different cartridges. Like I said earlier, the only evidence I will believe is photos of the bullet exiting the barrel showing what really happens to the PP. Until that happens everything we say is just speculation and theory. Anyone got a camera with a photocell trigger or video camera that is fast enough that we could use pull a couple of stills out of it? I did try an experiment of making a large tube [aprox 9"] of white construction cardboard from Wally World and spraying adhesive on its inside surface to try to catch pieces and see how big and far they were from the muzzle. The experiment failed as the muzzle blast was too strong and blew the tube apart without capturing any paper pieces.
Its like the grease in the cast bullet groove controversy, I believe only some pictures will show whether the muzzle blast or centrifugal rotation removes the grease from the grooves. My lands are so shallow I hesitate to say the tradition of the lands 'cutting' the PP is working. Yet his 'strips' seem to be cut. I have examined what little confeti I have recovered and have not yet identified a piece showing grooves or lands because they are all too small. Just specks of paper really which tends to support the theory that the muzzle blast is blowing the patch off / apart after the bullet base exits. I next tried 'striping' the patches with a marker but all I recovered was some colored specs of paper. Again, it appears only pictures will show what is really going on.

montana_charlie
04-05-2009, 05:36 PM
He occasionally gets long strips of paper recovered in front of the muzzle. I never get anything but confetti so small that it is hard to see. He frequently can find the base 'twist' yet I again, never have. I have identified a fragment of a corner of the base paper a couple times. Obviously, something different is happening between our two rifles, shooting the same PP bullet, just loaded into different cartridges.

My lands are so shallow I hesitate to say the tradition of the lands 'cutting' the PP is working. Yet his 'strips' seem to be cut. I have examined what little confeti I have recovered and have not yet identified a piece showing grooves or lands because they are all too small. Just specks of paper really which tends to support the theory that the muzzle blast is blowing the patch off / apart after the bullet base exits.
I wonder (and this is pure speculation) if a difference in 'fiber' or 'grain direction' could be producing those extremely different results where he gets 'cut strips' and you get 'dust'.

Are you guys using the same paper?
CM

powderburnerr
04-05-2009, 08:07 PM
It makes a difference if you use a different weight paper as well as different granulations of powder , if you swat it hard fast you will not have as much evidence as if you swat it softly .. ie 3F vs 1F if you are using black , the diamater also plays in here as does the paper thickness , . If you shoot his load in your rifle and have a different result then its time to scratch your head.........Dean

Baron von Trollwhack
04-06-2009, 09:34 AM
FWIW, My own conclusion is that given a particular barrel and cartridge there will be no ultimate difference in accuracy between GG bullets and paper patched bullets. BvT

windrider919
04-07-2009, 03:27 PM
Replying to Montana Charlie: He is shooting my PP bullets (cast n wrapped by me) w/ 100% rag paper and 1/4 strength Rooster to glue the patch togeather. The only difference besides rifling is that I am shooting .458 Win Mag w/ smokeless @ +-1600 FPS and he is shooting a Ruger 45-70 at the same velocity. I am shooting Hogden 4895 and he was shooting IMR 4895. I use a standard primer but he tells me he was using a magnum primer. I also load a .030 PE wad under my bullets. As per accuracy, I am using a 1X4 scope on 4X and get 1" groups sandbag/bench shooting and he has iron {peep} sights. He still gets 2" groups! However, I am 53 and he is 40 and has much better eyesight.

montana_charlie
04-09-2009, 12:02 PM
He occasionally gets long strips of paper recovered in front of the muzzle. I never get anything but confetti so small that it is hard to see.
Are you guys using the same paper?
He is shooting my PP bullets (cast n wrapped by me) w/ 100% rag paper and 1/4 strength Rooster to glue the patch togeather.
Same bullets, same patches...then your barrel must be the deciding factor.
His strips are (obviously) being cut...while your paper is being subjected to something that 'grinds' it into dust.
You say the rifling looks shallow. Maybe it really is, and there is some 'slipping' going on.
CM