AR15 that cycles with subsonic .223
 

Yeah I know some will ask why :smile: While I like plinking with my 22lr conversion kits with subsonic ammo I hate how dirty it leaves the gun/suppressor and how much my eyes burn from the blow back of that sss 60grn stuff. So since I got my 7 inch 300 whisper to cycle with a short gas tube setup I figured a .223 should do the same. Its a 10 inch barrel with 1-7 twist and a gas port of .108 moved back 2 inches from a pistol position. It runs 55 - 80 grn bullets over 4.5 - 5.2 of trail boss. All subsonic and locks the bolt back on empty mag even without a suppressor. I had a gas block made up where the gas tube goes in on a angle, it makes it much easier to fit on the short setups, only needing slight bend to work.

Interesting. I didn't think that a subsonic .223 would have enough pressure to cycle the action. Did you have to use a low mass carrier or lighter than normal buffer?

While I don't imagine I'll build one, I am interested in the concept. Thanks for sharing. It always amazes me what people find out can be done despite the common belief that it won't work.

Nothing special about it except for the gas block and the port location, all standard mil spec 223 internals. :smile:

With a second gas block in the carbine position, it'd be a do it all gun. :uzi2:

Yup, I've already thought about that. I already have a 2 gas port 300 whisper ar15.