1908s were commonly rechambered to 8x57, the dimensions are very close. I just traded off a finish reamer that was used for that purpose and that purpose only, first for the original purchaser and later for me.
Also FYI, in the 2 1908s that I've owned, the grooves measured 0.327"-0.328" (same in 1 1888 Commission Rifle in my rack). In my early ignorance I had Bob Snapp rebore the first one to 9x57 and it was a real jewel although also a real thumper. The second one I shot in the original 8mm bore with 0.328" groove and had good results with normal 0.323" 8mm bullets.
Regards, Joe
