I Was thinking the identical issue. Minimal amp TIG welding may very well be the answer to simply welding the roll marks. What is the perpose of copper? Individually, I would not use a drill push. It could be performed, but I'd personally go the router or mini mill route. https://louisfhjih.cosmicwiki.com/1107427/indicators_on_colt_m16a1_for_sale_you_should_know