Re: Removing YHM can
I don't have experience with that can, but, in general, unless the threading actually got buggered (as in you cranked it on against its will), you would probably have success with heating the can where it threads on. This will expand the can, while leaving the barrel relatively cool, thereby loosening the connection. You can try a simple hair dryer. If that doesn't work you can go to a torch.
Obviously make sure the gun is unloaded, etc. before getting into it. You are, after all, dealing with the business end!