I was cleaning my 686 the other day and noticed some flame cutting on the top strap just above the cylinder gap. I bought the gun used, and honestly don't know if it was like that when I bought it ~1 year ago. I've shot many different loads out of it, 125 gr and 158 gr. My question is, is some flame cutting in this spot normal with revolvers, particularly a .357 mag or other magnum/high pressure cartridge? Is there anything I can do to mitigate any further damage? I know that the .357 maximum had issues with flame cutting, as does the 460 S&W with light weight bullets. Will I get less flame cutting with a heavier, 158 gr load that doesn't spit as much flame as a 125 gr load?