a friend of mine recently had a 10.5" barrel ar-15 upper made up for his papered legal SBR
on a lark we decided to fire a few rounds through the chrony.
we were shocked to see the 7.62x39 didn't lose much speed at all form the 10.5" barrel. we were sort of expecting the mv to plummet like the 5.56 does from a SBR--
wolf 122gr was pulling 2140fps avg
yugo brass was pulling nearly 2200!
154gr wolf was bumping 2000fps i think the best was like 1997fps
the bad thing is now i am going to have to plunk down that $200 for the stamp--LOL! tis one is loud--a can wouldn't be a bad idea either---LOL
anybody else fire a SBR/pistol 7.62x39 for muzzle velocity??