recently got a 9mm upper for my ar15/m4 carbine…im running a h2 (4.6oz) buffer now! can i get away with h2 buffer on 9mm upper or have to go heavier to 9mm (5.6 oz) buffer??? every time i go swap uppers…does the 1oz difference really make a difference???
Buy a 9 mm buffer; heavier and longer than carbine.
Run the right buffer. Those blow back 9mms have too much recoil to use a regular buffer. Guys used to break those Cavarms polymer lowers when they’d run pistol uppers and a regular buffer.
The length should be the same however… unless I’m missing something.
well right now! im running a H2 buffer in lower! question is now run a 9mm 5.6oz buffer or heavier? like 7oz. due to i ordered a thread adapter from 1/2x36 to 1/2x28 so i can put on my awc mk9 can…
I have been running a 5in 9m barrel with an H2 on a polymer lower for a couple of years. It functions fine.
The more recent 9m with a 16in barrel and heavier buffer seems to run smoother, but it is not as versatile when switching uppers. So stuck with the h2 in the SBR.
Slash on Sturmgewehr sells a 9Q buffer for 9mm uppers. Heavy buffers.com. I used one in my model 635 and it made for a smoother firing gun.
How does the Qbuffer one compare to using an A5H4? I know the H4 is lighter but other than that? All I need to finish my 9mm SBR build is the buffer as long as I have waited to get this thing together I dont want to bust bolt catches or have cycling problems making the wait even longer.
The stroke on 9mm is shorter.
The buffer needs to be longer to keep the bolt face from overrunning the bolt stop too far, which tends to break it.