Carbine buffer tubes size?

AR/M4 AR Technical Discussion
1

I am looking at putting a Magpul stock on my Bushmaster Patrolman Carbine AR15.

I don’t know if it has a commercial or MilSpec buffer tube. I’m guessing it’s the larger 1.17" O.D. commercial carbine buffer tube.

Is Colt the only manufacturer that uses the smaller 1.14" O.D. buffer tubes?

2

yours is commercial size. most professional grade aftermarket stocks are milspec size, but a couple make both sizes.

magpul offers both sizes in their CTR and MOE stocks, and vltor’s website says they do too.

good luck

3

Thanks, and Happy Thanksgiving.

4

According the the infamous “Chart,” the following use a Mil-spec receiver extension (buffer tube) :

Colt, BCM, Noveske, LMT, Daniels Defense, Charles Daly, S&W, Armalite, CMMG, Stag

These do not:

Sabre Defence, Bushmaster, Rock River Arms, Olympic, DPMS

5

Sabre is commercial for sure, recently swapped to Sopmod and required kit with new tube. Switching out the tube is easy and gives more choices in stocks.

6

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