CW40 mag question

[warbird1]

Went to the range today. Had bought two new mags for my CW40 and wanted to try them. Had one minor problem. One of the new mags would not lock back the slide on the last round. Otherwise it was fine. Upon returning home took them apart and cleaned them. Under inspection they appear identical. Confusing to say the least. No big deal but I still want to figure it out. Wondering if someone who has had this problem could point me in the right direction. Thanks.

[warbird1]

I guess I'm the only one.... Oh well I reckon I will mark that one as mag #4 and use it for practice only. That will work.

[Buzzard45]

I don`t have a cw40, or any 40 for that matter, so take my advice with a grain of salt,or sugar if you prefer. First thing i would do is switch the guts from a good mag into the bad one, then maybe just the follower. If that didn`t help then look for a slight bulge in the housing, a few thousandths of a inch might make a difference

[warbird1]

Hey thanks. Good ideas easily tried.