Magpul butt stock question
 

Hello,
I am thinking about buying a Magpul MOE butt stock for my RRA ET. However, I have to choose between the Mil-spec receiver extension tube and the commercial receiver extension tube. Well, how does one tell if they have a mil-spec or commercial tube?? Any markings?? Are the dimensions different??? Thank you for your help.

If you've got a RRA lower it should be a commercial tube. That's what mine was.

Mil-Spec diameter is 1.148" and Commercial diameter is 1.168" Commercial has a 5 degree slant back too, the Mil-Spec does not.

The squared off or angled end of the tube is the easiest ID.
From Magpul Website

The mil-spec is made of a more durable material w/ a higher tensil? strength. It can stand up to a higher amount of force before it snaps in half. I think its 75 pounds. Im going off of memory so my #s may be off.

All,
yep. I have the info I need and a new Magpul MOE is on the way. thanks again.

Ooops, not diameter, but width....sorry.