On Fri, 17 Mar 2006 20:27:02 -0500, Tony wrote:
Have you developed your methodology?

In my recollection, the 1927A1 bolt is a bar stock part , rectangular in
cross section with a round turned projection in the front about 2~3" long
that accomodates the ctg head at the end.

Yes.

If you heat treat after machining you will be susceptible to warping,
dimensional change, and scaling of your machined surfaces.

So, are you planning on surface , slot, & cylindrical grinding after HT?

Looking at it further, I was considering making the cylindrical part
seperate, and inserting it into the rectangular part with a
low-clearance fit and pins.

I don't believe the factory bolt was heat treated, really no need for it.
It's an unstressed part for a low pressure ctg. I also believe the extractor
is staked in place, furthering the need for metal that is suitable for
deformation.

In the current production at least, the extractor is held by it's own
spring tension into a t-slot milled into the bolt. I'm trying to think
where I've seen another like it but can't think of one offhand. But to
remove the extractor from the bolt, you merely lift it "outwards" with
the head of a cartridge and pull it forward. It doesn't come out in use
because the outward motion is constrained by either the receiver, and/or
the spring tension of the extractor itself.

I think any un-heat-treated steel available from 1018 to 4140 would fit the
bill.

Any thoughts about the 2-piece fabrication idea? Or, of I won't be heat
treating, then really could just do my offset with the 4-jaw; everything
else other than that extractor slot is pretty straightforward.

Thanks,
Dave