Only problem is the velcro on the back of the armor itself.....welll yeah.....
And another problem is the weight of the weapon may be too heavy for armor with just 1-2 coats of resin and glass, I coated my armor with 2 resin outside, 1 inside, fiberglass, then resin over the glass, and the armor is still flexible in some areas, it isnt flexy, but with say 20 pounds of force pushing on, it will slightly bend, so a gun hanging on for a long period of time may warp the armor, I may also say you might want to use something like a guitar strap, or normal straps, such as hot gluing the strap on the side of the gun, then when hanging around your armor, attach the other ends.
1. attach plastic 2 way clip onto gun.
2. take the 2 way strap and hook them to the gun
3. wear it
4. to take off, just squeeze and pull off.
A clean approach for the armor and gun. (by straps I mean straps like in shopping carts for small kids, those things, you can buy them at the home depot/lowes.)
I was too lazy to photoshop something nice, so I made it in paint