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grunz
11-22-09, 12:02
Does the fast twist of a 1/7 barrel enhance fragmentation effects of the light bullet?

USGILT
11-22-09, 13:54
Not sure if you are asking this question in regards to maximum fragmentation ranges or just against personnel targets in the open with no barriers. Here are the fragmentation ranges for various barrel lengths for XM193:

20" - 190m
16" - 140m
14.5" - 95m
11.5" - 40m

Barrel length does have an effect is stabilization/muzzle velocity. Average muzzle velocity for XM193 is about 3050fps out of a 14.5" barrel. So it's probably good to about 75-100yds for reliable fragmentation. Personally for a 16” 1x7 twist barrel I would use 75gr Hornady TAP or 77gr Black Hills red box for 'carry' ammo.

DocGKR
11-22-09, 15:53
grunz--Twist rate does not seem to effect fragmentation of 55 gr M193 FMJ; twist rate can alter terminal effects with some other projectiles.

grunz
11-22-09, 16:20
Thanks DocGKR.

By the way are you ever on Calguns?

DocGKR
11-22-09, 19:34
I have not ever posted there.