To me, efficiency is the best ratio of pressure to velocity.
If you can get more velocity with less pressure, the load/cartridge is more efficient.
Comparing a so-called Magnum to a so-called Standard cartridge, if the larger Magnum case will get you more velocity, and a flatter trajectory at the SAME pressure, it is more efficient.
The Magnum cartridge does burn more powder, but what do you want? A safe load, with greater performance, or an economical one?
Economy is a desirable thing too, but if you need/want greater performance than 280 Remington, the 7mm Mag. will provide it at the same pressure level as a 280. Or, 280 performance without half trying.
You may prefer the 280 for some other good reasons, including economy, but �efficiency� the same thing as economy, is it?
Smitty of the North
