I'm not sure if this reg seat o-ring is supposed to be placed in the brass reg seat holder, or in the recess of the rear half of the valve. Pls see pics.
I've been placing it in the brass reg seat because that's where it was located when I disassembled it for the very first time, however...
...it keeps ending up here after a few shots.
Does it belong in the rear half of the valve?