Ok, just got some pin gauges and measured my gas ports (11” x39 Bren 2Ms):
#1. @ 0.0745” (1.89mm)
#2. @ 0.097” (2.46mm)
My Bren has not had any extraction / ejection issues after @ 1,200 rounds, though I have not checked the angle of ejection since it wasn’t malfunctioning. Will check next time I shoot it.
How does your rifle shoot on setting 2 adverse... I can see the shorter 11 inch bren functioning fine on setting 1 being 1.9mm but setting 2 being 2.4mm seems like to much gas to function reliably even with a dirty action.
1.9mm seems like it might be too big but it's probably ok for the shorter dwell time in the 11 inch barrel. I found the shorter barrel brens are tuned more appropriately and seem to experience less gassing issues due to the gas port location and dwell time.
Also what year was your gun manufactured.
Mine is from early 2019.
Honestly, I haven’t shot it on Position #2 as my gun performed perfectly well on Position
#1. It’s a 2020 vintage CZ Bren 2Ms.
