Where do you find the "substantially more case capacity" that you speak of?
The 260 holds 54 grains of H2O and the 6.5x55 holds 56 grains of H2O. What is a 2 grains capacity advantage, 3.57%, going to get you?
Assuming that the 1 to 4 velocity increase to case capacity increase rule of thumb is accurate, a 3.57% increase in case capacity would calculate to a velocity increase potential of 0.89%.
At 3,000 fps, 0.89% is 26.7 fps. Fast barrel verses slow barrel verses higher/lower outside temperature verses ???? territory.
Love the 6.5x55, currently have 9 of them, but the numbers don't lie. The only reasons that I, personally, would opt for the 6.5x55 over the 260 are:
A. The rifle that I want isn't available in 260.
B. I must be able to shoot bullets over 140 grains without having to seat them more deeply into the case. COAL issues you know.
C. I was going to use it in Europe or Africa, where 260 ammo probably isn't commonly available and the 6.5x55 Norma and RWS is more probably available.
JEff
