what are the PSI's

AR/M4 AR Technical Discussion
1

I would like to know what the PSI’s are at the end of the gas tube or at the gas key for rifle, mid and carbine? Thanks.

2

IIRC, according to Patrick Sweeney it is approx 1200 PSI for the rifle and approx 2000 PSI for the carbine. The mid length should be somewhere in between.