Mil-Spec vs Commercial
What is the difference between the Mil-Spec and the Commercial Receiver Extensions ('buffer tube')? Who uses what?
The commercial tubes are slightly larger in diameter where the stock slides, but slightly smaller in diameter when it screws into the receiver. Either can be installed on standard lowers, with the Mil-Spec one actually having the stronger interface (more surface area of the threads engage the receiver).
Mil-Spec ( 1.148" outer diameter): Colt, LMT, CMT (Stag, S&W, CMMG), VLTOR
Commercial (1.168" outer diameter): Everyone Else (Bushmaster, RRA, DPMS, Olympic, etc.)
This post was edited on 10/22 at 1:18 pm