Oh, one other thing I always do with any new-to-me 52 or 52 magazine:

I go through many rotations (minimum of 5, each with 5 in it) of loaded ammo hand-jacked through the pistol with safety on and pointed in a safe direction, mimicing the feed, extraction and ejection cycle. This, accompanied with a dial caliper is my method for "interviewing" magazines I have recently acquired BEFORE driving an hour to my range.