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Can one of you experienced builders give me some advice please? I'm in the process of rewelding an M53 receiver. The three rear receiver pieces have been welded. The rails fit nicely inside it and the bolt glides smoothly through it.

Today, I tacked the shroud to the rear and bolted in the rails to check the fit. Everything seems fine except the alignment of the tabs on the insides of the rail and the camming piece. I'm not sure they are okay. Do the rail tabs need to be exactly centered on the camming piece tabs? The tabs inside the cam are wider than the tabs in the rails and as you can see, they aren't perfectly aligned. However, the bottom face of the rail tabs does not extend below the bottom face of the camming piece tabs. Is this acceptable or do I need to fix it? Both sides are the same but I could only get an acceptable photo one side. I also installed the barrel and cycled the bolt to see if the rollers would lock and they did. However, I noticed that the bolt head jumped slightly when the grooves engaged the cam tabs.
If y'all think I need to fix this alignment problem, then I have another question. The photos below show that the rails are tightly touching the top inside surface of the receiver. I can't move the rails ups to improve the alignment problem. And yes, the rails are located on the correct sides. The thinner portions are up under the feed tray section of the receiver. So my question is how do I improve the alignment if it is needed? Grind some of the metal of the top of the receiver so that the cam drops lower? Or grind the tops of the rails a little thinner?
Thanks in advance for the help

That is correct and it looks good. The bolt head is just aligning itself in the trunnion. If everything moves freely with your fingers you will have no problems

Thanks a million Oakrodent. Huge relief. Maybe I'll be shooting this baby in a few of weeks.

Hi Doug,
Considering your question on alignment,The second picture shows the rear section somewhat higher than the camming section .As the sections are only "tacked" it may help the alignment to re-tack the sections with the rear section somewhat lower. Hope this helps.
later,cz2

Thanks for the reply CZ. Actually, lowering the rear sections would make the alignment problem worse. The bottom surface of both the rail and cam tabs are flush. If I lowered the rear section, the rail tabs would be lower than the cam tabs rather than more centered on the cam tabs. I took the photo close up of the rail and cam with the gun laying on it's side so when you look at the photo rotate it counter clockwise in your mind to get an idea of what it looks like when the gun is being fired.

Also, after Oakrodent replied that I was okay, I welded it up today.

Then, I worked on making the charging handle function smoothly. When I welded in new sections of the receiver and ratchet plate, the welds filled up the two grooves. It took several hours of careful work with the dremel tool and a cut off blade but I got it moving fairly smoothly. Tomorrow, I'm going to machine a small strip of steel that I'll wrap in sandpaper and use it to get the grooves back into shape. On my next M53, I think I'll machine a copper bar that fits in both grooves so I don't have so much work them cleaning out.