Chrome Lined! Yes! I always wondered if it was- it looked like it but I never had seen an article saying they were. But the bore looked like my old Japanese Arisaka(sp?) the 7.7 model that is chrome lined. Spent case has a mark but faint. I wondered about headspace too. I brushed out the bore and cleaned the breech thinking that might be it too but no luck. I'm not sure what the problem is. Thing shot fine for a good while, then I let it set for a year probably and then no luck. I still question grease or something. I guess I am gonna have to dig further in the gun.