Hi, what I have found to work best for my gun (UTG MK96), is to disassemble your cylinder and remove the cylinder head. Then, on the threads of the cylinder add some teflon tape. Also, if you can, take out your barrel assembly and try to wrap electrical tape all in little groups around the outside of the inner barrel. These will act as barrel spacers unless you have some. The makeshift barrel spacers will hold the barrel in place and reduce the barrel wobble.