Bwana-be

While your analogy on the 300 Win and 300 RUM is close to the mark there is one big difference. The 300 RUM comes in rifles at the same price as the 300 Win and cost of ammo/components, while more expensive, they are still in the same league.

However a 375 H&H, and lets be realsistic, 99% of them are M70, CZ etc, are far cheaper than getting a 378 and of course the difference in ammo/component costs is very great.

Mike

Fostech, if your main question is why you don't see more talk about the Weatherby than the H&H, then you have to take into consideration how much history and nostalgia lie behind the H&H. In a sense, it was THE Mother Magnum. For a long time, it was the 30-06 of Africa, and owning one meant something, even if you never planned to get on a plane.
The fact that it did its job so well is lessened none at all by the fact that the Weatherby shoots flatter. The Weatherby was invented to go faster, and that's what it does.
You could compare the sentiment many have about these two cartridges with those of the 300 Winchester vs the new 300 RUM. There is no doubt in anyone's mind that the RUM will go faster, or heavier if you prefer. But given that the Winchester does such a damn fine job, there's alot of folks just don't see the point in trading the trajectory for all the recoil and noise.
If you want the fastest 375, then you know where to get it. If you want a fun cartridge that will damn sure get the job done, you won't regret the H&H. (And we won't give you too much of a hard time when you rechamber to 375 Weatherby!)

To me a 378 WBY mag is strictly a handloading proposition!

you guys are sick.....
woofer

Once you get to the 378 recoil level, one is tempted to look at 416s...I think its that simple. For long shots at plains game, a 416 pushing a 350 grainer at 2600 fps shoots flat enough to take all of the guess work out of 300 yard shots, and only 2.5 inches lower than the 300 gr 378 zeroed at 200 yards. Yet a 416 with 400 grainers at 2400 fps is much more appropriate as a DG stopper.

There is a world of difference between the 416 Rem burning 80 to 85 grs of powder and the 378 burning 110 to 115. The 378's expansion ratio is right near the 300 weatherby, and reduced loads are inconsistent. If you are a handloader, the 416 weatherby is a better choice for reduced loads as it becomes a 416 Rigby...that's very good company and the reloading data can be directly substituted.

The all-time sleeper load for the 416 Weatherby is a custom 500 grainer at 2400 fps...The SD is so high it will penetrate as well as a 400 solid and expand to 1 inch while doing so. Yes, it will loosen your fillings, but then a 378 will do the same thing.

So, the 378 is a fine round but it is not all that flexible. Since it does not download well, you must take the punishment while giving up the DG stoppping ability of the 416s.