Took both ends of a grease gun and cartridge gun and could not get the cartridge gun. Tried to pull it out with a pair of locking pliers. Still won't come out. Anybody face this problem before and how did you get the cartridge out. Not a cheap gun, the other one went in the trash. Thanks for any assist you can give me. Thought about getting really long screwdriver between the cylinder and the cartridge and break the bond. Frank