so does 300 black like pistons or no?
I thought we all collectively moved past the piston AR fad at this point? I know there are a few high end AR's that use piston but, I think this came out of the now dead and thank god it's dead "M16 VS AK" debate from like 20 years ago. I have heard "oh yeah if you are running a slower projectile like 300BLK you're gonna want that piston" and also heard "oh yeah if you are running suppressed you're gonna want that piston" and exactly the opposite from other sources. I don't think I have seen evidence supporting which one is correct at this point. The only thing I recommend based on personal experience is an adjustable 300BLK gas port especially if you have a short 300BLK. Is anyone actually using a longer than 16" 300BLK barrel?
I have both a pistol length gas and a long-stroke piston .300 BLK upper. I've run them both suppressed quite a bit. I default to the piston (PWS Mk109) because I don't get gas in the face shooting it suppressed. It is a slightly heavier upper and has a bit more felt recoil. I only run supers. I've tried subs, but since I'm not using these rifles to sneak into a building and murder folks I don't care about sound signature. I've not found one type of piston to run this particular caliber, suppressed or not, better than the other.
While I only have a sample size of 2, I can promise you either one will run reliably with a can. Personally, I think .300BLK is a niche caliber that's best in suppressed SBRs. Yes you can run 16+ inch barrels but I think there are other, far superior calibers at that point in the AR platform.
Speaking of HSTs, would 147gr HSTs be a good option from a 16"+ PCC barrel? Goal is to have some stopping power within 50-100 yards at the most.
Initially thought about going for 124gr +P HSTs but that velocity could get in the way of proper expansion, so leaning towards the slower 147gr now.
I'd like to remind you that pistol rounds, even out of longer barrels, will certainly kill but they're nowhere close to centerfire rifle rounds in terms of lethality or "stopping power." What stops any opponent with a projectile weapon is CNS disruption (the only OFF switch type effect) or blood loss (more of a dimmer switch type effect). So without being terribly pedantic, don't be too concerned with "stopping power" of a round, which similarly to "knockdown power" isn't quite correct. Instead, experiment to find which rounds
run reliably in your weapons and then train to be capable of getting multiple rounds into opponents' vital areas quickly.
I've seen more than a few people shot multiple times with pistol rounds come into a hospital. The ones that actually made it off the operating table only had a few rounds in them in non-vital (heart, lungs, liver, CNS) areas. The one time in the few years I've been in the OR that I saw someone make it into a room with multiple pistol rounds in the high chest/neck area, they didn't last long at all. Nobody shot in the upper torso or head with a rifle round(s) that I've heard of entering the hospital ever made it to the OR.
