ORIGINAL: oldelkhunter
I get a little over 2700 fps using a max load of RL-22 (47gr)and a 140gr bullet out of a 29" barreled swedish mauser, you can load another full grain of the same powder in a stronger action, but the velocity gain isn't much. A 6.5x284 from all accounts pushes the 140 gr bullets around 3000 fps.
I am going by my Nosler manual and comparing a 140 grain bullet and there was 100 fps. 2900vs 3000 ..... I have to look this manual over again when I get home.
Ok I looked at Nosler number 5 at home and the max speed for the 6.5x55 with a 140 was 2785 vs 2925 for the 6.5-284
The comparison of the 6.5X55 vs the 6.5/284 is exactly the same as comparing the 6.5X55 OR 6.5X57mm with the 6.5 Remington Magnum or the 6.5/'06. The .284 Win case has the same capacity as the .30/'06 case, but in a shorter, fatter container. It is prized for its accuracy potential, not its' ability to produce high velocities! There is no reason why the 6.5X55 or the 6.5X57 would not be just as good, except for the need to use a longer action for the latter two rounds.