I am saying that the chemicals necessary to strip nickel from a barrel do a lot of bad things to the barrel. However, normal gun barrel solvents will loosen powder, copper, or nickel fouling equally well. Using those solvents in conjunction with proper brushes and patches will clean the barrel well to a point. For a hunting rifle that does not get a lot of rounds put through it, this should be fine.Are you saying normal gun barrel solvent will not work a chemical especially made to remove nickel should be used or if you have stainless barrel just repeating brush and patch with no solvent or standard ok?
But if you shoot a lot rounds through a barrel such that either copper or nickel has fused to the barrel metal, then you have to chemically remove that metal from the barrel. Hence the reason for the development of copper fouling removers like CR10, Sweets, Patchout, etc. Those copper fouling removers won't work with nickel. In fact, they are specifically formulated not to attack iron/steel, nickel, molybdenum, or chrome in our barrels.