He is out of commission with a severe back injury. Are you going to do the repairs yourself?thanks for the links this gives me a place to start.
i do know that i do need some lube to remain in the crosshatch to lube the seal.
these seals are for a pellet gun, the maker is Jim Maccari.
What is the barrel made out of? It seems like the surface hardness of the bore is too low.the other thing that puzzles me is with the 400 grit crosshatch after a few hundred rounds thru the gun the crosshatch is gone and the cylinder walls are polished to a mirror finish.