Thread: 300blk vs 6.5 grendel with short barrels

Yes my 24" Grendel (RIP black buddy) flung factory 123's SSTs @ 2550fps and I could emulate that with hand loads. @dogmatix got 2200fps from a 16 inch barrel so a 10-12 is likely to be slow. And forget subsonics, even if you get them to shoot ok they will only punch a 6.5 cal hole and unlikely to expand. 6.5 bullets are designed for super sonic speeds.
I would go 300BLK every time for such a short barrel. It uses fast rifle/shotgun powder and mine could fling 130s at 2200fps out of a 12.5" barrel so slightly more energy than dogmatix 6.5 with a 16". However I loaded it with Speer hollow points which expanded fine out to 200m on goats. Also it could shoot 200 - 240 grain subsonic projectiles which also worked fine at close range. Never stumped up and purchased Lehigh projectiles, cast lead holowpoints expand well enough.