[Jeff Higgins]

Wind drift, tabby, think wind drift. Heavier for caliber bullets, with their higher ballistic coefficients, don't stray as far from the intended path for a given side wind. Makes it far easier to stay on target in gusting, unpredictable winds. In no wind or a steady wind it makes no difference, but we rarely have the chance to shoot in either at long range (1,000 yards).

The bigger cases come into their own by launching heavier bullets at the same velocities as the smallers cases can launch lighter bullets. For example, my .45-100 will start either a 540 grain Paul Jones Creedmoor bullet or a 550 grain Hoch at almost 1,300 fps with 90 grains of Swiss 1.5 Fg (equivilent to GOEX 2 Fg). To achive those velocities in the .45-70, I have to drop down to the Lymann #457193, a 420 grain bullet. The .45-70 will barely break 1,100 fps with either of the two heavier bullets, and is actually not even legal for NRA long range at that velocity (.45's have to start a 500 grain or heavier bullet at 1,200 fps of more, due to impact angle in the target pits). The ballistic coefficient of the two heavier bullets is somewhere in the high .400's, approaching .500. The 420 grain bullet is in the low .300's. The difference in long range performance is very noticable.

So, you are quite right in that foot pounds of energy mean nothing in target shooting. However, aerodynamic performance does. That is what we are after with the heavy bullets. And it takes more powder to launch those heavey bullets at the desired velocities. It has to be the right powder, though. Fg often wont give those heavy bullets the velocity they need, even from the biggest cases. Best to stick with FFg (GOEX) or 1.5 Fg (Swiss).