1-8 vs 1-14 twist rate for a 22-250

J

jcm412

Inactive
Can someone please explain to me the major differences between a 1-8 twist rate and a 1-14 twist rate for a 22-250.

Thanks

P.S. does anyone know a good dealer for custom heavy barrels?
 
The heavier (actually longer) bullet to be shot, the faster the rifling must be to stabilize it. A standard 14 inch twist .22-250 is a hunting rifle good with bullets up to 60 grain flat base. An 8 inch twist barrel would let it handle 80 grain boattails for target shooting at ranges of 600 yards and up.
 
It may not. My M70 22-250 with 14" twist shows best accuracy with 63gr Sierra. As a general rule, I think twist does matter, but individual rifles may vary.
 
With the .22/250 the standard 1:14 twist is best for small projectiles, up to 50gr, for bullets up to and including the 60gr (i.e. Nosler Partition), you are best to use a 1:12 twist. The fast twist 1:8 & 1:7 are designed to shoot the long 80gr Matchking and other VLD bullets.

The big problem with a fast twist barrel and small bullets (which will have a very high muzzle velocity) is that the velocity obtained with give an extremely high rpm rate to the bullet, with the chance that the bullet will disintegrate under the rotational forces and not reach the target.
 
To answer the second part of your question, Shaw supplies threaded and short-chambered barrels in five contours. Their straight (26 inch - 1.250 diameter - 9 lb) barrel is suitable for bench-rest work. I don't have accuracy results yet because the rifle is still a-building. I'm using 1-14 twist for the 50-55 grain bullet weight range. And yes, I did limit myself by choosing this twist. With a faster twist (1-12 or 1-10) heavier bullets (60-62 grain) could be used, but that remains to be seen. Velocity is a factor also and as has been stated bullet construction is important also. Rotational forces - or rpm - will destry a poorly bonded bullet.
Brownells also offers barrels made by Shilen. If you have access to machining facilities, their straight unchambered unthreaded barrel is hard to beat for the price.
Standard factory twist for the 22-250 seems to be 1-14. Anything faster would seem to be a after-market item available from any of our many barrel makers.
Good luck
 
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