35 x 338 Ultramag
In the process of adapting my lefty 700 ultra in 338 to a properly headspaced cartridge, I got a zip spindle and 35 cal eliptical exp. from Hornady. I then necked up the virgin ultra cases, and then proceeded to neck them right back down, leaving a false shoulder at the crush fit junction. This way my cases stayed put against the bolt face. I couldn't do anything about the over diameter chamber in the Remmie, but the circlip ext. kept things pretty well centered. Point is that it's not much problem to neck em up to 35 cal.. Question is, are there really very many bullets that will take the spin and velocities of a 35 cal ultramag?
Even with the orig. 338's, over the counter bullets are questionable, and there's a bunch of 35 cal. slugs out in the market for 35 Rem. and 358 Win.. So why not flip a coin and go with one or the other of Rem's ultras, the 338 or the 375. Best of all, they still handle like any ordinary mdl. 700 magnum rifle. But I have to admit, that the 35 cal neck mod in my virgin 338 Ultra cases, makes for one mean looking customer.