On Mon, 8 Apr 2013 17:14:22 +0000 (UTC), Cydrome Leader
wrote:

RogerN wrote:

I'm close to milling my AR lower receiver, this "95%" machined receiver
needs a pocket for the fire control group and 3 holes cross drilled for 2
pins and a selector/safety.

I found some instructions for machining the pocket using a DRO, they
recommend drilling the selector switch hole, machining the pocket then
drilling the trigger & hammer pin holes. Why not drill all 3 cross holes in
that 1 setup and then machining the pocket? I would think the drill bits
might be more likely to walk as they start through the 2nd side. I don't
see a benefit to set up for drilling, turn turn the part for milling, then
turn back to the first setup to drill 2 more holes, any idea why they would
do, or recommend this?

https://colfaxtactical.com/docs/Fire...%20a%20DRO.pdf

RogerN

does anybody make plastic unfinished lowers, just for machining practice?

It would seem like a shame, and expensive to be using trashed lowers for
the next aluminum casting project.



Buy a 0% forging, make a mold from it using bondo (autobody filler)
then make some machinable wax castings from that. Screw it up, just
remelt the wax!

Remove 333 to reply.
Randy