I'm not sure about what this question is referring to. If the same velocities are produced with the same barrel length, then assuming equal bore quality, the Ruger will typically have lower pressure because it has a larger capacity. A larger capacity can use a slower powder, resulting in lower pressure.what about pressures and stickiness in hot weather?
Now you've touched on something...talking about a "good" rifle. One of the reasons I shoot the 375 H&H is that I shoot it in a Sako safari, with quarter rib in all its loveliness. It is not an "affordable" gun as others mentioned, but man does it float my boat! (functions flawlessly, too)
I've reloaded .375 H&H for a while and haven't noticed that case life was limited. In fact, I was just wondering the other day how long they'd last. Seems to me that I've reloaded a lot of cases 5 or 6 times and they don't look any worse for wear. They don't seem to require case trimming either. Once trimmed to the standard length, they tend to retain that length after shooting. Does anyone else have the same experience?
It would depend on how hot you load the cartridge. A moderate/medium load will result in a long life for the cartridge case.