david doyle hit the nail square on, shoot the heaviest bullet that your rifle shoots well and that you can handle the recoil of. With 6.5s it is very easy to get to maximum pressures very quickly with intermediate powders, and therefore usually end up with lower velocities when within acceptable pressure ranges. If you're shooting an M96 or M38 or M94 6.5x55 Swedish mausers or Norwegian Krag or any of the others out there with weaker metallurgy, be very careful to stay within the pressure limits of the loading manuals. With newer actions such as Remingtons, Tikkas, Winchesters and several others, you can very carefully work up loads that are substantially hotter if you feel the need, The 260Rem is already right up there at the 55,000 psi level and quite an impressive performer. Most 6.5 rifles are very accurate as long as the throats aren't way out there and have a decent twist rate. The military versions will usually have a 1-7.5 in twist, Remington and Winchester 1-9.5 in and most European non custom rifles will be in the 1-8 in, give or take range. A lot of custom rifles are in the 1-12 in range to keep pressures in check and velocity up, these rifles will sometimes shoot up to 140 grain bullets, but prefer 129grn and less. Make sure that you know what your twist rate is before picking the bullet you want to shoot. Slower powders like W760 or H4831 seem to work well with all weights, but faster powders can be used with very good results with lighter bullets and slower twist rates. For ball powders, I prefer to use magnum primers (better consistacy between round to round velocities, my personal experience) and for extruded powders, I use standard primers. Enjoy your 6.5. bearhunter
