[Guest]

potentially dumb question... how do i determine what type of buffertube i have, commercial or mil spec? i accidentally purchased a magpul buttpad for the CTR (in my defense item only said ar15 buttpad with a small pic)which is fine since i was planning on gettin the CTR anyway, problem only being if i get the comm version it comes with the buttpad...
so how do i know which to get??? thanks in advance

 

[Guest]

calipers ?

Bushmaster uses commercial sized receiver extensions

 

[Guest]

quick response, but bummer

 

[Guest]

Everyone like Rock River uses commercial. Only Colt/FN or Military contract uses the smaller tube.
The inside diameter is the same so you dont have to worry about the buffer or spring. The walls of the
commwerical are thicker so the out side diameter is larger except for the threads that attach it to the reciver,
the threads are the same.

 

[Guest]

Everyone like Rock River uses commercial. Only Colt/FN or Military contract uses the smaller tube.
The inside diameter is the same so you dont have to worry about the buffer or spring. The walls of the
commwerical are thicker so the out side diameter is larger except for the threads that attach it to the reciver,
the threads are the same.

+1

Couldn't have said it better myself. Thanks for saving me all the typing.

 

[Guest]

I know stag, CMT, LMT and I think DPMS, CMMG use mil spec buffer tubes.

What you need to do is measure the outside diameters. Then do a Internet search to find the exact measurements.

What brand rifle do you have?

 

[Guest]

It's real easy, if the BT is the same size as the threads - Commercial. If it has a shoulder and then tapers down immediately after the threads - mil-spec. about 90% of the BT are commercial.

 

[Guest]

Explain this to me please? WHY IS THE MIL SPEC THINNER?

 

[Guest]

Explain this to me please? WHY IS THE MIL SPEC THINNER?

everything you ever wanted to know

http://www.m4carbine.net/showthread.php?t=101