On May 2, 12:12*pm, "
wrote:
The barrel has male threads and screws into the receiver's female
threads.
The shoulder of the barrel stops at and presses against the end of the
large ring of rifle receiver.
Some rifles have an inner "C" stop ring that is where the breech of
the barrel presses against.

Newer cheaper rifles do not *have this feature.
I is very hard to machine this feature into a receiver.

TIA
Clark

I assume you're talking about Mausers with the inner diaphragm.
Mostly this is an aid to barreling, in theory, all spare barrels can
be chambered to the same depth and they'll work, an advantage with
military arms. Everyone else's had to be checked and headspaced with
a reamer after barreling since they seated on the barrel shoulder, not
the barrel end. These days with a Mauser action, you can check gauge
protrusion with a depth gauge on the old barrel, chamber to the same
specs on the new barrel in the lathe and theoretically have the same
headspace when the new barrel is wrung into the receiver. Assuming
the original headspace was correct, of course. The only thing that
beats it is the Savage-type barrel nut. There's some gas-handling
stuff that's better with the Mauser system, too. Like you say, it's a
hard-to-machine feature, most current made Mauser-type actions either
don't have it at all or it's been modified for production and doesn't
do everything the real deal Mausers do. Ludwig Olson wrote a pretty
good book on Mausers and their action features. It's an expensive
proposition to duplicate all the features of the action these days.


Stan