Breech Plug Gap

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Buckskinn

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I just noticed an issue and I have no idea how it happened but need opinions on how to fix.

As picture depicts I have a gap behind the plug that is about the thickness of 4 pieces of paper. I swear it wasn't there when inletting, but it is now...

20200220_201840.jpg

Should I just skim bed that area? I have some stainless epoxy that I've used to bed bolt actions.
 

Walkingeagle

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Did you keep any shavings from the woodworking process on this stock when inletting? If so, make shims and glue into place. Once dry, remove excess and rough sand. Final sanding will come far later in the process.
Walk
 

EC121

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The screw head looks a little high. Make the countersink for the tang screw deeper in the front or make the screw flat bottomed in a drill press or buy a flat bottomed screw that only hits the corner of the countersink. The contact angle of the tang hole and screw is pushing the barrel forward.
 
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Flintandsteel

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The counter sink will make ZERO difference. It's still a tapered hole, and no mater how deep you make it, the taper is the same.
You NEED to move that barrel back. In recoil, that small gap can do lots of damage.
Is the barrel pinned yet? If so, that gap will at least bend the barrel pins.
Best fix? Pin the barrel first, then plug and redrill your tang bolt.
If you don't want to do that, shim the wood behind the barrel.
Pin the barrel first.
 

EC121

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The counter sink will make ZERO difference. It's still a tapered hole, and no mater how deep you make it, the taper is the same.
It will make zero difference if the two angles(screwhead shoulder and countersink) are the same and perfectly centered. Also if the screw is at the proper angle to the tang. We don't know that. He said the gap goes away when he removes the screw. So, something in that area is off. Maybe the countersinks don't match or maybe the tang bolt angle is pulling the barrel forward.
 

billraby

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First thing I would do is to cover the tang bolt with inletting black and put it in. Stop as soon as it snugs up. Have a look at where the bolt is making first contact. Then do it again and tighten it down. Its not a fix, but it will give you an idea of exactly what is going on. Work on a solution from there.
 

tallpine

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The barrel moved when you drilled the tang hole. Probably all you need to do is open the hole in the stock a little. Use a round file or drill out the stock with the next size up drill bit. Easy fix
 

Scota@4570

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There is a good chance the tang bolt hole is a tiny bit forward. Take the tang bolt out it out and see if the barrel can be moved back. Re install the bolt and see if the barrel moves forward. If so drill the hole out a hair larger. The bolt should not be bearing on anything.

Be careful the bit is not sucked in and ruins your stock with the drill chuck. To prevent this lessen the angle on the cutting edge of the bit . Just touch each edge against the grinding wheel. Making the underside of the cutting edge parallel to the length of the bit will do it. This is a good tip for soft metals too.
 

Buckskinn

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I put some prussian blue on the bolt and it is definitely rubbing on the muzzle side of the hole, pulling the barrel forward. Also checked the tang with blue and that all looks good. Weird thing is that the barrel moves away from the stock more than the back of the tang does. Can barely get a piece of paper in back of the tang and about 4 thicknesses of paper behind the barrel. I don't know if the tang is flattening a little making up the difference or what. The gap at the tang end would easily be made up with finish swell I think. But not the other issue...

Since I had some room to play I tried to open the front of the countersink up a little bit without it going oblong. I am at about the diameter of the screw head now, so can't do much more there.
 

EC121

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What about the angle of the screw itself? Due to the angle of the threads in the trigger plate, it may pulling the tang forward.
The tang may be flattening because there isn't any wood under it. Wouldn't take much of a gap under the tang to let it flatten.
 

SDSmlf

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When you put the countersink in the breech plug, did you use the same setup as when you drilled the hole through the tang and stock? If drilled hole(s) and countersink are not in line the head of the screw could be drawing the tang to the center of screw/countersink hole. Try putting a washer under the head of the screw (may have to use a longer screw) so the countersink is out of the equation when you tighten down the screw. If it doesn’t move the barrel, your countersink and hole through the stock are not lined up or concentric with each other. If so, there are a couple of easy remedies.
 

Buckskinn

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It seems that is the issue. I believe my countersink is angled too much toward the buttstock causing the barrel to move forward slightly. It did not move forward with a washer above countersink. And as pic shows it rubbed off the blue on the barrel end of hole 20200221_161620.jpg
 
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