Brownells M4 Receivers

[prepare]

Does anybody know who machines the Brownells M4 receivers? Are the done in-house or out-sourced?

[Five_Point_Five_Six]

Aero Precision machines them. Brownells confirmed so on TOS.

ETA: Aero machines the lowers, the uppers are machined somewhere else.

[bigjoe7757]

I don’t know who machines them but I just used one and it was GTG.

[kwg020]

My LGG carries Aero. I have done several builds and have been completely happy with them. Brownells front door is 52 miles from my driveway. I would not be afraid to use anything with Brownells name on it.

kwg