I also got this, painted it black and now can only chamber one round, no option to load ammo

i have this same problem BUT it can happen while im on an empty server by myself

feedback.dayzgame.com/view.php?id=6825

When you kill a player, it ruins most of their items including guns. However guns do not display their condition yet. Ruined guns cannot fire and this can happen with any gun. Spawned in guns that cant fire just spawned in a ruined condition.