Salvaging a relieved .303 barrel

maple_leaf_eh

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I've been given a 1954 dated Canadian No.4 barrel. Great! They aren't making these any more. This barrel was removed from its original receiver by CAL when they converted the rifle to 7.62. When they removed it, the standard practise was to saw cut a thin shallow slot near the receiver ring. That cut is what bothers me. How can that slot be repaired so the barrel can be reused? Secondly, who can do this work for me?
 
a few ways really,

The way tiriaq discribes is by far the simplest way.

If the grove was deeper then the threads
make 2 rings correct id and od, cut them half a blade width off center so there is no gap then just soldering them into place. then machine the knox flat again
 
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I had thought of that in my post before i edited it, but id assume the grove is a smaller diameter then the threads.

If not, then thats definitely the most simple way
 
Cutting a relief groove to relax the torque on the shoulder is a very common procedure when dealing with No. 4/P'14/M1917 rifles. Reduces the risk of tweaking the receiver.
The groove can be cut with a hacksaw, parting tool in the lathe, etc.
Turning the shoulder back makes for a nice clean repair. The breeching washer gets sandwiched between the new shoulder and the receiver ring, and allows the barrel to be pulled up with proper torque. If a hacksaw was used, the ring may be no more than 1/8" thick; if a parting tool was used, somewhat thicker.
 
I'll put up some pictures, but to answer the obvious questions.

The cut is quite narrow, almost a slice with a knife or a hacksaw. I can't imagine a lathe cutting tool being that slender.

The cut is maybe 1/8th inch deep, and it is so close to the edge of the shoulder, the metal has dented inwards.
 
Just true to that mark on the lathe, and then run a reamer for proper headspacing. You may be able to take exactly one thread at a time to get the extractor notch in the same spot.
 
Just true to that mark on the lathe, and then run a reamer for proper headspacing. You may be able to take exactly one thread at a time to get the extractor notch in the same spot.

This is an option. It requires a reamer, of course. And if the rifle is in service configuration, the forend and handguards will be too long, and will have to be altered. If the rifle is a sporter, the new chamber will probably be smaller than the issue one.
 
This is an option. It requires a reamer, of course. And if the rifle is in service configuration, the forend and handguards will be too long, and will have to be altered. If the rifle is a sporter, the new chamber will probably be smaller than the issue one.

If its one thread on a 14TPI barrel, your really only loosing 1/14 of an inch. I'm not sure where you would have to remove material on the fore end if any at all, but it is something to consider.
 
If a 1/16" relief cut (hacksaw) was made, 1/16" from the face of the shoulder, it would require at least 1/8" (.125") to be removed from the barrel shoulder. That is more that one turn, which is about .070".
How much clearance is there between the front sight guard and the caps on the ends of the front hand guard and forend?
I have done this, and had to set the caps back.
 
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