I’ve found a (new) 404J barrel I can get cheap. It is threaded for a 1917, I want to fit it to a 98. It also has a 1” threaded locking nut like a savage in front of the receiver thread. I’m thinking I could turn it down and cut a 7/8 unf thread in it and make a collar from 4140 and loctite it on. This would leave 0.126” of minimum chamber thickness, I’m thinking this is a bit low? Or maybe 15/16”-20 with a minor diameter of 0.878” and resulting wall thickness of 0.166” but would this leave enough meat in the sleeve at the receiver threads?

Or can you turn a 1917 thread down for an M98? From what I can tell minor of a 1917 is 1.085”, which with a little diameter growth due to threading isn’t far off the 1.100” nominal of a 98… does anyone know the cartridge protrusion, cone and extractor cut depth on a 1917?

From what you describe I would set the barrel up and turn the face back until the breech face is cleaned up, turn the threads down and set the shoulder back. If the minor is 1.085, then you would be fine to turn to 1.100 and proceed.

The Spec minor on the Enfield is 1.060 - .005"

Mauser Spec is 27.94 - .15 on the major.

As long as you keep your pitch diameter tight, it would be unsightly, but functional, and according to (Ackley was it?) safe.

i had a somewhat like situation - it was supposed to be a 17 barrel, which was easier to recut for a small ring, which I promptly made into a 308 -- turned out to be a 14 barrel, and keyholed 308s .. off with that barrel, on with a Douglas 358 win

quote:

Originally posted by Fal Grunt:
From what you describe I would set the barrel up and turn the face back until the breech face is cleaned up, turn the threads down and set the shoulder back. If the minor is 1.085, then you would be fine to turn to 1.100 and proceed.

The Spec minor on the Enfield is 1.060 - .005"

Mauser Spec is 27.94 - .15 on the major.

As long as you keep your pitch diameter tight, it would be unsightly, but functional, and according to (Ackley was it?) safe.

I’ve just got some more details - it’s slightly worse. 1.052” minor, and once the extractor cut and cone have been faced off the resulting tenon is 0.404” long before the OD drops into the 1” thread. Going on a LR 98 thread pitch of 0.083” that’s 4.8 threads. And at 1.052” major, it’s not ideal. Shame

quote:

Originally posted by brnomauser:
This would leave 0.126” of minimum chamber thickness...

If you figure the barrel is decent steel at around 130KSI yield, then .126" wall with a .55" hole gets you about 60KSI chamber pressure. That is basically zero safety factor. It might be fine for black powder?