I wanted a way to hang my singlestack magazines on the steel door inside my ammo cabinet, so I quickly whipped out this. It uses both M4 heated inserts and some strong rare earth magnets, so it might be a bit over engineered, but this is he way I wanted it, and the materials I had at hand.
The magnets I use (2x32mm nedymium magnets) are definitively overkill, so you can probably get away with less, or maybe even stong doublesided tape.
There are two versions, the regular have a bit of retention, and the loose box should have a bit looser clerance to make them easy to get out.
Tested with 9mm 1911 magazines, but should to my knowledge also fit .45