Nitro-X You're right about the .375 Ruger and the .532" base diameter, rather than the 8x68's .522". I was quoting the only source I'd seen on it and that was Scovil's writeup I looked at in a grocery store - Handloader or Rifle mag. : The only .375 Express I am aware of, as a registerd wildcat, is the .444 Marlin case necked to .375 - by Ken Waters. This cae, at 2,23" length, could also be made on 8x57 or 7x57 brass for a rimless variation. Also, there is a .375 Express, or 'Payne' Express on the .348Winchester case. ; A Water's type .375 Express using 7mm or 8 mm brass would be most similar to a 9.5x57, a standard European round.(Water's version is an improved-type case, with a .454" to .456" shoulder, standard for the Ackley Improved rounds on standard brass. The 9.5x57 has a smaller shoulder. ; Knowing Corbin to be a wildcatter - I'd guess it was the Water's version. Excellent choice, BTW, with case capcity listed as being 68.55gr. total.
-------------------- Daryl
"a gun without hammers is like a Spaniel without ears" King George V