Element nozzle are main O-Ring are off spec. You need a bigger O-Ring. If ind P14 o-ring are suitable for RA-Techs but not imperial ones is better, Im too lazy to dig up the spec if you want pm me. Remember if there's too much space between the inner BCG and O-Ring seal wont be effective and it will just burst out. Another thing is that its misaligned. I know Element spec aint that great, I got 4 (it was cheaper than purchasing new shells and O-Rings at the time)
As for replying to about AGM, another problem is the spec and QC, I know stock tube isnt really smooth as it should be so yea.
as far as right now, Im taking a break on GBBR, (just sold all my mags to fund my ptw, usp, and school)