Cracked Dust Cover

[Garrett]

I posted a week or two ago about the problems I was having with my old sight on my open gun, and that it was time to upgrade. You can read about it here.

I finally bought a C-More and a mount and was ready to switch out. When I pulled the old mount off though, I discovered that I had a crack in the dust cover coming out of the rear scope mount hole.

I was talking to the gunsmith today about welding it up and he noticed that there was a hairline crack on the other side of the dustcover as well. Additionally, welding may be difficult, as the frame has been hard chromed. The added chrome content can cause problems when welding.

While a cracked dust cover is not unheard of, I don't see how that would be a high stress are of the frame. The extra weight of the scope & mount probably didn't help. But with them removed, should the cracking stop?

I was thinking of fitting the upper assembly to a new frame, and building this frame into a backup Limited gun. I'm hoping that with no extra weight on the dust cover, it should be okay.

I know I have heard of other people's dust covers cracking. Does it generally stop after cracking so far (especially after removing the scope), or should I expect it to continue cracking? Can I expect any problems to arise from shooting the gun with a cracked dust cover?

Rather than fitting my slide/barrel to a new lower, I'm thinking about mounting a Doctor/J-Point/Optima type sight on the slide. I think there should still be enough material on the rear of my slide for this. I'll have to think about that for a while, though.

Any comments? suggestions?

[Heath]

I've never welded gun frames, so I may not know what the hell I'm talking about.

If the gun is hard-chromed, then it's likely that would affect the alloy content of the filler metal used while welding. The impact of additional chromium is that it will increase the hardenability of the steel. While this might sound ok, it means that it'd likely be more prone to cracking without some sort of heat treatment. Preheating the part to be welded can reduce the likelihood of hydrogen cracking. I can't say how much preheat is necessary because it'd be impossible to estimate how much chromium would end up alloyed into the filler metal. Another course of action might be to grind away the hard chrome near the weld and then have the frame re-finished afterwards.

It seems to me that the hole could be plug-welded with a copper backing plate and then re-drilled if necessary (the weld bead won't stick to the bacling plate). The challenge would be managing the heat so as not to distort the frame rails during the process. Oxy-Fuel welding is great, but TIG might be more suited to this purpose. While you're at it, you could possibly plug-weld all the holes and then go to a Docter type sight.

[Nolan]

I've had my old Caspian frame welded up in 5 places. It was plated with a Chromium Carbide finish. Gary at Caspian had me send it to Accurate Plating in Florida. They stripped off the plating, welded up the cracks and then replated the gun. No problems until the comp finally cracked.

From the looks of your frame it wouldn't be a problem to have it welded up.

I don't know if Accurate still does the warranty work for Caspian. The website is

Accurate Plating and Weaponry

Nolan

[GuildSF4]

Maybe the quality of the photo, but a couple holes look out of round/not straight in... Just wonder if like Benny said this cracking may be caused by too light of a spring and the weight of the scope... Just guessing on that.

The Doctor mount by Beven is awesome BTW...

[jjanglin]

Look at the other posts

Jim