On Sep 4, 7:19 pm, "RAM³" wrote:
trg-s338 wrote in news:3fd333a7-0b99-4d89-8b66-
:

Some rifles have the bolt engaging lugs machined directly into the
barrel itself. I've been informed that some replace barrels in such a
system by cutting off the lugged section of the old barrel and
threading that onto a new one. Is it really that difficult to
directly machine lugs onto a new barrel and thus eliminate this
creation of a third part, a barrel extension AR 15 style? Can this
replication of the original barrel be done by a home machinist? What
process and tools would be involved, perhaps some internal grooving
and metal shaper work to cut the lugs or is it much more involved?
Any perspective on this would be appreciated. Thanks.

A dumb(?) question he Are the Lugs you're talking about the one(s) on
the *outside* of the barrel that take the bolts/screws that attach the
stock?

Normally, those would be the only ones *on* a barrel as opposed to the
Locking Lugs on the Bolt.

If you're talking about the recesses machined into the barrel that
*receive* the bolt's locking lugs, the operation would, normally, be
performed at the time that the chamber is bored.

Attempting to "splice" a barrel would require an absolutely perfect match-
up between the rifling of the two pieces - the retained chamber section and
the new barrel section.

RAM: To clarify, I meant to say that the "recesses machined into the
barrel that receive the bolt's locking lugs", as pertaining to my
inquiry. Apologies for the inaccuracy of terminology. So the reaming
of the chamber would be done first and the dimensional machining of
the recesses done next to get it as close as possible to the proper
headspace?

Ed Hunter, Bruce from Bankok: That is an interesting twist (pun
intended) on the locking lug design, but how would limit the tightness
of the bolt lock on the head of the brass (headspace)? I seem to
recall somewhere a post on a threaded bolt with flats ground on
opposite sides to allow withdrawal of the bolt, as I understand it.
Was that from you Bruce?

ksdg another poster, references the "old Savage bolt action 23A, the
barrel and receiver were made out of one piece of steel. There was no
joint between barrel and receiver. They seemed to shoot very
accurately." A variation in design that would indeed promote
alignment and rigidity in the system but probably not a good system
for barrel burner cartridges.

I suppose headspacing adjustments on a recessed barrel would be a
matter of grinding and lapping the lugs until a perfect fit is
acquired on the gauges. The design of current Savage bolt action with
the barrel screwed in or out to achieve perfect headspace and then
lock ringed in place is looking more and more a convenient and
practical design, accurate too from what I've read. I'm just not
clear on how the "moveable bolt head" contributes to the accuracy
potential of the design.