I've looked at charts but have a hard time believing a 1-7 twist in 5.56 only works with 68gr and up bullets.Not a lot of 1000rd cases of that for sale I can find.Would a 1-8 or 1-9 be preferable providing we ever get to shoot them again? I'd rather shoot 55gr.
rate of twist
- Thread starter mbogo3
- Start date
BattleRife
CGN Ultra frequent flyer
- Location
- of No Fixed Address
Shoot what you want. The idea that overstabilizing a bullet is somehow bad for it is grossly exaggerated, unless it is overspun to the point of disintegration. A 55 grain bullet through a 1-7 twist barrel works just fine.
Bingo. It seems to only REAL issue with spinning a bullet too fast is the potential for it to come apart. C-fbmi was blowing up bullets when he built his 22 baboon, but that was a 22-284 spitting them at ridiculous speeds with a relatively fast twist barrel.
It might not be ideal for accuracy, but if you're looking to buy bulk ammo I doubt you're concerned about that.
Charlie Brown
CGN Regular
- Location
- Campbell River
I have shot thousands and thousands of 55gr through 1:7 barrels; no issues whatsoever.
The only thing Ive ever heard about negative is keeping the lights going 3000 or under to reduce copper fouling in a 1:7...not sure about reality vs theory but havent been willing to test it. 55 seem to shoot more accurately when I dumb down the load for my 1:7
redshooter
CGN Ultra frequent flyer
- Location
- Central Ontario
Too fast MAY cause you problems, too slow WILL if you want to shoot 62 gr or heavier. 1 in 8 is as slow as I'd go.
1-8 's are not as common as they once were.Bullet construction is a consideration as well but seeing we can't hunt with most of these guns anyway.The Hornady SX will not make it 100 yards until it becomes dust.Speed does the same thing with them.A buddy found out that from a .220 Swift back in the day.
Gunnerlove
CGN Ultra frequent flyer
- Location
- Vancouver Island
1:8 will easily stabilize 77gr match bullets which is why most match barrels are 1:8. My 1:9 Stag would as well (stable and grouping well at 500m).
1:7 is an Army thing tied to stabilizing super long 62gr tracers at -40C. Milspec.....
1:7 is an Army thing tied to stabilizing super long 62gr tracers at -40C. Milspec.....
At close up distances like 100-200m, I've shot 52 grain flat base, 77 grain SMK and 80 grain with no difference in pure accuracy out of 7.7 and 8 twist barrels. 55 grain is more drifty at longer distances of course, but i haven't experienced huge group size variations.
