I was questioning a similar factor. Low amp TIG welding could be the answer to just welding the roll marks. Exactly what is the perpose of copper? The "C" on the barrel would point out a chrome chamber only barrel. But AFAIK, Colt marked the "C" up near the muzzle https://marcossqok.wikimillions.com/3543928/the_smart_trick_of_colt_combat_elite_commander_45_acp_that_no_one_is_discussing