[Thor]

I have been told to clean a 22 much less than a center fire, the residue and bullet grease go a long way to protecting it. I would clean mine once a year if used a lot. The lead bullet (except stingers) is much easier on the bore (friction wise) than copper gilding metal, I believe. I do think that copper and the moisture residue are not good for a barrle and the copper should be taken out within a couple of days to prevent a dissimilar metals battery type oxidation-reduction from setting up. All combustion produces water so the less of that left in the barrel the better. I do believe WWI ammo was more corrisive (I see less minty WWI original barrels than WWII ones) though a lot of 1920 Commercial 30 lugers have damn fine barrels. Thor