Optimum 300BLK Barrel Length

[Tim]

Use Case:
- I have a spare SBR'd lower
- I have a spare .30cal suppressor that is obnoxiously long and heavy (AAC 762SD)
- "truck" gun that will probably just live in the safe, but let's me say, "yeah, I have a truck gun"
- subsonic critter/miscreant control for all those times I run into zombies and have my truck gun with me

So, what's the shortest viable barrel for reliable cycling?

Ideally, I'll be able to find/build a piston operated upper (JAKL?) so I can really really have a cool folding stock truck gun (that lives in the safe...)

 

[Supermatch]

8" gets my vote to keep OAL down. You shouldn't have any cycling issues even with short barrel lengths, i.e. 6". Even the Honey Badger is only 7", and the pistol variant is 6".

 

[steelciocc]

I support @Supermatch ‘s thoughts. I have that same can on an 8” ACC built DI upper and have had no problems with subs or supers. Surprisingly quiet with subs!

 

[Icculus]

I say 9" and a standard length offered by BCM