Gents, has anyone ever chronographed the muzzle velocity of federal tru 64 grain sp out of a 10.5 barrel with 1/9 twist? Would be a big help.
EDA: A nice guy at the range let me run 10 rounds through his chrono. Below are the number.
Extreme Spread: 78.8
Standard Dev: 24.4
Average Dev: 18.4
This was out of a factory Rock River SBR, 10.5", 1/9 twist, Chrome lined barrel,
65 degrees outside, 160 elevation