Caliber change opening up bolt face

themouser

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Hey cgn wondering where I can go in lower mainland to have the bolt face done? Also does bolt have to be rehardened after machining? Going from 223 to 762x39
Thanks
 
If I were you, I would be looking for another bolt.

I opened up a Remington 223 bolt face to slightly over the "standard .480" diameter, to .485 for a wildcat using the 6.5x55 case. We won't go into how smart that was. The bolt/action were freebies.

The bold faces are HARD but they can be cut without having to "soften" the metal first.

The process is tedious and time consuming to say the least. Then of course, you also have to cut a new extractor relief for the new extractor ring you're going to have to purchase or have your bolt modified for a different style extractor.

In the end, it's going to cost you about as much as you can purchase a used short action rifle for, which already has the proper bolt face and rebarrel it to accept the 7.62x39

I know that I wouldn't want to attempt the job again myself.
 
Opening out a boltface counterbore is not uncommon. The extractor is going to need to be adapted as well.
I had a Ruger 77 opened from .308 size to belted magnum, and installed a magnum extractor. No big deal. The bolt was machinable.
The extractor situation with a Remington 700 conversion is more complicated. I had a M700 bolt with a spoiled .222 counterbore. Had it opened to 7.62x39/6PPC, with a Sako type extractor fitted. There are serious implications if this is done, because the safety breeching inherent in the R700 is compromised. Set up a R700 with 7.62x39 barrel as a project, lost interest, set up another in 6PPC, lost interest in that one, used the receiver for something else; still have the bolt somewhere.
Basically, the bolt is stripped, and a spud installed, which is centered up in the chuck. The bolt body is supported near the head with a steady rest, and an appropriately ground cutter used to do the face.
Specialized milling style cutters can also be used.
The make and model will certainly be factors in whether or not the conversion is practical.
 
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