This is not a bug. It may be an incorrect use of syntax or a limitation in the software. For further discussion on the matter, please consult the BYOND Developer forums.
I've ran into some sort of BYOND Bug. My guns exceed the 32x32 boundary, so they are multi-tiled. When I try to pick up a gun I only pick up the part of the gun in the original 32x32 area. The rest stays behind as a split gun.