[Henry5001]

I think they could break down. If you don't repair they will
1. Load less ammo from boxes
2. Less damage
3. Maybe misfires so you freeze and take like .5

Maybe you could make a repair shop, you pay 10 dollars to lay your guns down and make like stocking except you're repairing your gun.
For example, you gun has detoriated a little bit: You walk into the repair shop, lay your gun down, and press A until you reach 25/25. However if you didn't repair it and it damages more then the number goes up so you might need to get 50/50 or 100/100