many weapon models such as the pump action shotgun, derringer and m79 (but there are others, i believe the bk18 is one) where when you load into the game with one in your inventory that has a round chambered, the model is glitched, sometimes with the shell floating next to the gun (like with the pump action or derringer) or other issues, such as the m79 appearing normal but if you eject the chambered grenade, you will see it's facing the wrong way (towards the player instead of out the barrel, lol.)