I compete in a ligue of old timers shooting old guns(before 1900)and we can only shoot lead bullets with metallic sights.One class(Cowboy)is for lever guns.Most of us shoot 30-30.My model 64 Winchester always start good but its flimsy 24in.bbl starts sending them left and right when it heats up.Last year,I bought an octogon 26in.bbl and had it installed on a Win 94.The bore was,well I'll say neglected and that's being very very kind to the previous owner.The first slug I pushed in didn't show any rifling marks on it.Dang!I've been had!About 4 to 5 hours of JB compound through it finally gave an engraved lead bullet pushed through it but I could see that the grooves were still rough.And the shooting prooved it.Shooting 2 dozens of J bullets didn't improve things(6 to 8'' groups at 100).Disgusted,I put the thing in the gun saferoom and tried to forget it.
A few months ago,after accidently leading a bbl,I had a stroke of genius and fired 4 or 5 low vel bullets with GC.Bingo,most of the lead was gone and my cleaning job was much simplified.I decided to apply the same remedy to my 26''bbl and it now shoots like it should(2 1/2 to 3'' at 100).
Even at the high price they're fetching nowadays,I don't see these GC as so expensive afterall.