Built one a couple years ago for an elk rig. SAAMI chamber, but ended up with a fairly tight one. I do like the beltless design, and it seems pretty efficient and decent ballistics w 200gr.
Guess 8mm will always be the red-headed stepchild of the rifle world. As Al said bullet selection ain't great, even in hunting bullets. Nosler AB and Barnes TSX 200s shoot about equally well, with IMR4350 an 4007sc, respectively. It will just hold MOA at 500 when God is smiling. I gave up pestering Ty at Barnes about a 200 gr XTC, or whatever they call those tungsten-core dudes. I'm probably too cheap to buy enough to work up a load, even if they did make them...
I had a few boxes of Speer 200s left over from my 8 Mag days - well seasoned. Burned some of them up in barrel break-in and initial load testing. Looking back, I see they shot pretty danged well, for not even messing with them much. I sprung for a box of Nosler partitions and see they're nearly identical in dimension. I'll try those next. I've fought bullet runout in this rifle, and think I may have finally solved that with a different die set, and slightly different sizing proceedure.
Unless someone is nutty enough to bring out true benchrest quality bullets in 8mm, I think this caliber will be more at home in a hunting rifle. I think most big bore long range guys are looking for a higher node than this chambering is likely to provide.