I understand 50-- that type of shot would only be taken under the most ideal of conditions/setups-- something we come across occasionally up in the mtns. A steady 10mph x-wind will move that bullet 20" @ 600. The only real answer to the limit of one's ability to shoot at any particular range is experience. I guess then the only way to find that answer is to get out and see what can be done under field conditions-- something i intend to do in short order. Thks. for the reply.
If concerned about penetration at impact, go with the 140gr SST. This will provide you with an accurate hunting bullet that will penetrate at those velocities. Also, the BC should be higher then the Amax giving more retained vel and energy at impact.
My steel targets at 600yds show some very nice craters from Saturdays testing. It should have no problem if it encounters a shoulder.
You might have to back down your present load a bit as these SST's are longer - longer bearing surface.
Or - if you want a really heavy bodied bullet you could use the 140 Sierra gameking. I get the best accuracy with these in most of my 6.5's. Used this one in a 6.5x55 on a couple elk. MV was 2725. One @ 100, another about 135 yds. Both went clean thru - no evidence of expansion but end result was good.