What justifies a magazine catch
 

to be worn out and in need of replacement. My luger I shot often I have noticed that there is a little bit of play when the magazine is inserted and the magazine catch, catches and locks in place. I can push up on the magazine just a tad bit more. Is this common or should it lock in place and have little to no play in it.

I would guess the issue is the magazine is worn rather than the mag catch....

Most all Luger magazines have this little bit of play/movement in them. I think it's part of the holdopen. The follower button interacts, is springy and the play is allowable .

Yeah, what Jerry said.