the only time I would expect to see such flame cutting would be when shooting really hot +p+ loads or boatloads of the hotter Corbon or Buffalo Bore stuff; I would expect it more in aluminum framed guns, but if this was a serious concern I feel that S&W, Taurus, and Charter Amrs would put a stainless steel gas shield just above the gap between the cylinder & barrel as S&W does for their scandium/aluminum alloyed revolvers chambered for .357 magnum