Well, on a good day, there's sun power to spare and I feel ok enough to go play in the shop, even start a fire over there and wait for it to warm up a little bit.
I wanted a way to hold brass (for the 6.5x55 but this will do any ~ .470 base brass) really straight and no slip to turn the necks over a mandrel. I had the tool (I think I got it from Sinclair, but who knows, it's been around awhile),
and made a mandrel for it the right size - .002 under the caliber, and set the cutter for 12.5 mil thickness with a feeler gauge.
So, since they don't actually make a collet like I wanted, I decided to modify a standard 3/8" ER 40 collet to put a little .472 step in it. That was a real job. I tried to soften the glass hard steel with my oxy acetylene torch, no go, though I melted some corners. It must air-quench and I didn't get the entire thing yellow hot, just a quarter inch around the part I wanted to cut.
Chucked a 3/8" blank in there to hold it all centered, sized, and tight for no chatter, and proceeded to knock the flutes off a cobalt drill. Oh well, put in a diamond wheel in my toolpost grinder (which should get its own thread).
Even at slow rpm and insanely low feed with lube - diamonds come off, not much metal.
I'd bought some cheapo little solid carbide endmills on Amazon, sold for woad carving (!) which is also where that spindle motor came from, and tried one of those, at 45k rpm and real slow feed.
Yep...this worked, but it ate yet another of those out of the pack of 5. Glad they're cheap ...
So, this thing lets me quickly chuck in brass to a known stop, and straight, so I can turn it over a mandrel I made that's the same size I use in the internal neck sizing die I also made, all perfectly straight and not too difficult.
The surface finish is nice, and the precision is also very nice, I can set thickness easily to tenths accuracy.
Probably the most expensive in time and money tool ever used for this, depending on how all the tools and supplies are amortized, but a guy needs a hobby...