So the one VM that was having trouble split the chamber (for the pistons) at the spot where it is brazed onto the barrel. It happened early on and it still ran 3 1/4 dram and heavier loads even while it was broken. With two chambers and two pistons, even if one breaks, it still runs.
Good Shooting, MarkCO
.40 S&W Club #1, 1911 Club #1067
NRA Life Member and Certified Instructor