Bwana-
While I was in Germany I met Michael Uekoetter; an engineer who "invented that wheel". He calls his cartridge the 7.62UKM (Uekoetter/Katzmeier Magnum). Katzmeier is a friend of his who works for H&K. He also developed the 7mm Katzmeier which RCBS sells dies for.

Michael and I fired his UKM at a 1000meter match in Switzerland. We both did well. We didn't get a group size, just a score. They were using an electronic scoring system that showed you your hits on a screen and gave a numerical score. I was in the middle of the pack and it was the first time I had ever fired beyond 300m (and that was for M16 qual).

If you're interested, I'll try to find info. I lost track of Michael a couple of years ago. If I can track him down, he could probably help you get dies at a good price, since they're no longer custom order from his supplier.

Here's some basic info:

7.62mm UKM (.338 Lapua shortened to 57mm, necked to .308)
168gr Sierra Match King: 77.0gr MRP 3300fps-Max.-25"bbl.
185gr Berger VLD: 74.5gr MRP 3149fps-Max.-25"bbl.
190gr Sierra Match King (Moly): 74.5gr MRP 3129fps-Max.-25"bbl.

Dont we call this the .300 Rem Ultra Mag.

Yup, that looks like it. Thanks for the info.
I'll play with it a bit, see if I can maximize the theoretical design, try to build it in the next coupla' years.
And like I said, just because you can get the same speeds from other rounds doesn't make them the same. Otherwise the PPC would be replaced by the 243 W.
After looking over the wins from this past year's 1000yd games, it looks like 30-cal mags are fairing very, very well. Especially in score, but even in group.

http://www.angelfire.com/ma/ZERMEL/762ukm.html

Close, but not quite the same as my drawing. Same basic concept, but mine has minimal taper, sharper shoulder, a bit shorter body, longer neck, designed for 3.1" COL w/o intruding on powder. If the data on the UKM is true, mine should do much better than I thought, with less barrel even.