I had a M4 in “worn” condition, was working fine then I tried to reload a new mag and it wouldn’t let me. I opened my inventory ad it appeared there was no magazine in the rifle. From there I couldn’t combine or attach a magazine to the gun. The only way I found to resolve this was to find a new m4. When I found a damaged m4, it let me load the mag in to it but wouldn’t let me reload my “worn” m4. This has happened to me several times. Also, My teammate picked up the bugged rifle and it made his AK completely disappear