I’m new here but no stranger to Savage firearms. Having owned several different models. I recently purchased a 110 L in .264 that shoots great (pre 1968). #409xx. Bore sighted and looks great for its age. Only problem is the bluing has some spots that need “touch up”. When using Birchwood Super Blue it just doesn’t work at all. I used the right alcohol, washed then heated area and cotton balled the spots, let sit 30 mins rinsed and lightly oiled but it doesn’t do anything. Looking closely at the areas there is no rust but what looks like a stainless type finish piercing thru. Can that be why the cold blue doesn’t work? Any advice would be greatly appreciated.