AR15 Buffer Q

[CelticArmory]

Ok, this is for all the AR gurus out there. I know there is a difference between the AR15 Rifle length buffer and the Carbine length buffer. I know there is a weight and what appears to be a length difference. I changed my barrel from a 16" HBAR to a 20" CMMG light weight barrel some time ago and had cycling issues that I resolved by removing a weight from the buffer. But I would rather put the right stuff in the rifle.

I want to get a rifle length buffer but my question is, will it work in the 6 position carbine stock or will I need to get the fixed rifle stock? I've not owned a standard rifle and haven't handled one since basic training back in 88 so I'm not sure if there's a difference in the buffer tubes on the two types.

 

[Bartholomew Roberts]

I want to get a rifle length buffer but my question is, will it work in the 6 position carbine stock or will I need to get the fixed rifle stock?

A rifle length buffer will not work in a carbine stock. It will only work in a rifle length buffer tube, which is typically found with an A1 or A2 fixed stock.

I changed my barrel from a 16" HBAR to a 20" CMMG light weight barrel some time ago and had cycling issues that I resolved by removing a weight from the buffer.

A rifle buffer weighs around 5oz, compared to 2+ oz for a carbine buffer. If you solved the problem by removing weight from the carbine buffer, then a rifle buffer is probably not going to help you. However, if you want the weight of a rifle buffer in a carbine stock, the H3 buffer is similar to the rifle buffer weight.

 

[Zak Smith]

There is likely something wrong with the upper assembly causing your problems. A properly-built upper 14.5" up to 20" should work fine with a rifle receiver extension & buffer assembly, or a carbine receiver extension and buffer assembly.

-z

 

[Zerodefect]

what ammo are you running?

 

[AR-15 Rep]

Keep in mind... rifle length buffer= rifle length tube= rifle length buffer spring.
Carbine length buffer= carbine length tube= carbine length buffer spring. Not sure why the rifle did not operate with the different barrel.

 

[CelticArmory]

I'm not too sure, but it would frequently short cycle. Didn't matter what ammo I used, mil surplus, HSM or my own reloads. It acted like either it wasn't getting enough gas or it had to push too much weight. Admittedly the front sight may be off by .020". When I ordered the barrel assy I ended up ordering a round end cap but needed a triangle one. Since it is a lightweight barrel the barrel hole in the end cap needs to be small, but when I got a triangle end cap all I could find were the larger ones for government profile and HBAR. So I cut the round cap and used it in order to attempt to center the triangle cap. I really need to get CMMG to send me a triangle cap with the smaller hole.