The thing is, IMO, that if one leaves copper solvents in the bore too long and too often, one may well be incurring unwanted damage from that. Unintended consequences in the form of microscopic etching of the steel which in turn promotes increased copper fouling- a catch-22 situation. I've heard this theorized by knowledgeable folks over the years and lean toward believing it. Not all of my shooting is with cast bullets, and when shooting jacketed stuff I never leave the copper solvent in the bore more than 5-10 minutes then run a series of dry patches, and repeat the cycle as necessary leaving the bore clean and oiled. Sweet's 7.62 Solvent and Barnes solvent are my two poisons of choice for that. Strong stuff, either one.
As for not cleaning a hunting rifle after sight-in for the duration of the hunt, that's my protocol too. Another trick I have been known to do is to clean normally and oil, then before hunting remove the oil and finally wet a patch with acetone or brake cleaner to leave a chemically clean dry bore. I found first shot impact to land right where it's supposed to. The downside to that is risking rust if conditions are damp. Other compatriots of mine scoff at both protocols and clean and oil and then go hunting. They maintain that risking slightly off bullet placement on a deer-size target at 50-100 yards is nothing compared the risk of a rusty bore. These are the same fellas who tell me I overthink this stuff too much. Perhaps they're right!
Finally, if I had a persnickety rifle like the OP's I probably wouldn't futz with it anymore and re-barrel it. I've sold guns for lots less reasons than that too. Life is too short. I certainly wouldn't have endured the gun's shenanigans for 15 years- he's a better man than I for that reason!
Last edited by gnoahhh; 06/15/16.
