Welding an old Bomar cut

[Rapier]

Have you ever gotten one of those old 1950s version Bomar Target rear sight cut slides in for a low ride sight replacement? At first I told the guy there was nothing I could do with it, because I did not want to fool with it, really. I mean that old sight had a cut that was over a half inch in width. I knew it just had to be welded up, but the chances of a real screw up was there in spades. So the guy just would not leave it alone, finally, I told him I would fix it if and only if he understood it could warp, the metal might not match, the metal might harden to be super hard, etc., etc. I could try to reblue it and if that did not work I would have to sand blast the blued Colt slide and coat it, yes, yes, yes and I knew he just was not quite listening to everything I told him, he was expecting a diamond and it might be scrap. Gun owners are strange that way.

So as I do not weld myself, I took the slide and the 65 degree fill bar to a buddy of mine that has a full shop including an argon MIG welder. Cut the bar off a bit short, for filling by weld, he tacked it to the back of the slot (the slot has to be moved forward also) and it matched up exactly with the old flat. The fill and the weld was going beautifully when he decided to fill just one more little spot at the rear of the slot filler and there was a blast like a 22 shot and we had a glob of molten steel down the rear of the slide. I thought the slide was destroyed so I bought the guy a new 1940s Colt slide figuring I was going to need to replace it. Then I got to looking at the old slide closer and thought, what the heil, you can probably fix that with the files and tools you have. So I started with the files and my horizontal belt sander (for major excess) and the diamond wheel for the motor tool, got the excess weld off, recut the top of the serrations and cut the glob of steel off the rear, then hit it with some Oxpho blue and it all blued to match, I was on the right track, better lucky than good. The gunsmith welding rod and the slot filler sold by Brownells blue to match a 1911 slide, at least this one. Next I reduced a motot tool cut off wheel in size, reduced the height of the screw with the diamond wheel, and gently re cut the firing pin keeper notch on one side. At the top of the notch where the curve is, I used a carbide cutter in a motor tool to create the curve and to cut out the steel that flowed over the firing pin hole. When I was finished the firing pin plus spring fit like a champ and the keeper went in easily and locked in place. It actually looked good.

Then I used a file to adjust the front and rear slot cuts for a Novak front and a rear low ride adjustable sight.

When that was finished I used Ospho to remove the old blue from the entire slide. Washed it off with water, blew it dry and stuck it into a mineral spirits bath. Then set it out for a day to dry. I then lightly polished the sides on the buffer, taped them off and blasted the top and dust cover. After the blasting and polishing I gave the slide a bath in Acetone. Then I heated the slide up and applied Oxpho Blue, hit it with the carding wheel and applied several coats repeating the process of heat, coat, card.

Right now it is resting without oil to see if it will cure to a hard surface. My first trip with this stuff had the fresh carded blue come off with oil, leaving a gray slide. Moral to the story is that, it is possible to fix an old Bomar cut with the slot blank filler and a decent weld, plus a bit of elbow grease.

I will try getting you a picture of this project near finish and when put together, tonight.
Ed