I have some mags that feed properly in these old pistols and some that aren't as reliable. The more you shove into a mag.the more they stack in a curve and the more pressure (drag) there is on shoving a round forward when chambering. They stack nose down due to the rims stacking on top of one another. 22 full magazines is the nose down position of the top rounds. It's my opinion that the problem with the old PP/PPK/PPK/S. 32 ACP I would think the upper round would simply ride over the lower rim when shoved forward. Since rimfire ammo doesn't really have a square cut rim like. Rimlock is where the rim of the top round gets located and caught behind the rim of the round under it. Darned if I can make it occur even by trying.