I shoot benchrest.
I've got three calibres I play with with the BR rifle - 6PPC, 6BR, and .22PPC (0.070" short). The PPCs are the more accurate, but that's likely because of the use of the BR barrel is more toward varminting. My best small group to date in registered competition was 0.132" for five shots at 100 yards.
My 6PPC performs best with 68 gr. Barts Custom Bullets and a case full of H322 (I load to the point where I _almost_ am popping primers - the heck with those "moderate" pressures - the gun shoots well this way). I haven't chrony'ed this load, but I'm guessing I'm pushing it at about 3450 fps or so...
Many folks will discount the accuracy of these rifles after shooting 'em once - You've gotta either shoot on a calm day, or use wind flags, or you're going to have a lot of horizontal dispersion. I had several quarter inch groups at 200 yards at the Nationals this year that became 3/4" groups when I misjudged the wind... In short, these rifles will shoot better than you say that you can shoot after you've had a few beers with your buddies...
Other rifle calibres I've got are .308 (half inch accuracy in a Savage), .22-250 (shoots in the low/mid threes), .243 (currently becoming a 6/284), and a .223 masterblaster...