First if there is already weapon jamming ignore this post.
Second if there isn't what I would think it would be is a .5%-1% chance that when you fire your weapon jams. Meaning you would have to go through a lengthy (7-16 seconds) unjamming procedure this can be very critical. if for instance (real story of what happened to my grandfather) you open/knock down a door and there is a enemy there; with a grenade you of course shoot and your weapon jams forcing you to use the butt of your gun in a close combat to defeat the enemy.
Second if there isn't what I would think it would be is a .5%-1% chance that when you fire your weapon jams. Meaning you would have to go through a lengthy (7-16 seconds) unjamming procedure this can be very critical. if for instance (real story of what happened to my grandfather) you open/knock down a door and there is a enemy there; with a grenade you of course shoot and your weapon jams forcing you to use the butt of your gun in a close combat to defeat the enemy.