Wanted to ask if all AR’s chambered in 9mm have a standard thread pitch since most come with a flash hider....Thanks...Mark

Colt is 1/2 x 36. Some follow that, I've read some don't.

They can be found in 1/2-36 or 1/2-28, the latter is becoming more common for suppressor compatibility.

Mine is 1/2-28

Thanks guys. My lower that is on order is a PSA lower with plans to match it up to a PSA upper. I will try and call PSA on Monday to ask which pitch they use on the upper I am looking at....Mark

This message has been edited. Last edited by: sigarmsp226,

A quick peek of a couple 9mm uppers on PSA show 1/2-36 as the thread pitch.

Black92 - Thanks Sir...I should have looked at others uppers on their site before asking here....The one I was looking at did not specify and never thought to look at other units...Thanks Again...Mark