I have a Colt 7.62x39 barrel that I removed the FSB on and want to install a a low profile gas block using set screws. I went to dimple the barrel where one of the set screws is and it is right where the hole was drilled for the pinned FSB. Can I weld up the hole, grind it down, re-contour it on my lathe and then dimple it? I am not sure if the barrel is 4140 or 4150 or if that even matters.
Thanks.