On 12/27/2010 11:34 AM, David R. Birch wrote:
On 12/27/2010 7:16 AM, tnik wrote:
On 12/27/2010 7:55 AM, Karl Townsend wrote:
Record cold and snow in MN. I'll soon be locked in the shop for the
duration of winter and been casting about for a worthy project.

I came accross this:
http://www.dsarms.com/prodinfo.asp?number=1001

Is this a good forging to start with? Anybody else done this? Any
heads up for problems? Any fixturing suggestions? I'll plan on
building quality fixtures to knock 'em out on the CNC mill.

Karl


Drawing and machining a prototype lower was one of the first major
projects I had in Solidworks. I've always wanted to go back and redraw
it because I know there are better ways to get-er-done now. We started
out with a solid block of material. iirc it was at least 12 ops to get
it all done. Well, almost all done.. had to leave a couple holes out
since the ATF wasn't here to serialize it.

Any special reason you left the bottom of the mag well parallel to the
top? Some current mags wouldn't fit.

That was the way the customer wanted it. I had to reverse engineer one
that he brought us. I was lucky enough to find a dxf of an AR-15 so I
could get the proper hole placements and tolerances.


ATF doesn't need to serialize it nor do you if you're building it for
your own use. You can't sell, give away or otherwise transfer it unless
you have a manufacturer's license, which is when the serial number
becomes necessary, which the manufacturer does, not the ATF.

David




Exactly, this was an actual job we were looking at getting so if we went
into production of the parts (iirc) an ATF agent (or someone that could
do it) would have needed to be present during the final operation and
serialization.