Will a 5.56 can run 300 BLK or do I need a dedicated 30-cal?

This comes up a lot and the short answer is: **do not run 300 BLK through a dedicated 5.56 can.** The long answer is about why.

**Bore diameter:** A 5.56-rated suppressor has a bore of roughly 0.230". A 300 BLK projectile is 0.308" in diameter. The projectile will not fit through the suppressor baffles without impacting them, which is a baffle strike at best and a destroyed suppressor at worst.

**Subsonic vs supersonic doesn't matter** for this — the projectile is too big regardless of velocity.

**What you want instead:** a **.30-caliber (7.62)-rated can** with a bore large enough for both 5.56 and 300 BLK. This is the normal "multi-caliber" suppressor configuration and what most shooters running both cartridges buy.

**Good options in this category:** - SilencerCo Omega 300 (compact, reasonable weight) - Dead Air Sandman-S (shorter, heavier) - SilencerCo Hybrid 46 (the flagship multi-caliber — handles everything through .338 Lapua)

**The tradeoff:** A 7.62-rated can on 5.56 is slightly louder and slightly less effective at sound suppression than a dedicated 5.56 can, because the larger bore lets more gas escape. For 5.56 work specifically, a 5.56 can is quieter. But for your use case (both calibers out of one upper), the 30-cal can is the right answer and the sound difference on 5.56 is modest.

**Do not, under any circumstances,** try to shoot 300 BLK through a 5.56 can. The forums are full of stories of baffle strikes that destroyed the can and damaged the host rifle. It is an expensive mistake.