This is an unabashed plug for the Lazzeroni short magnums, which arrived first, and which offer very high performance. They come in 7mm, .30, .338 (for all of you who are cheesed off that Winchester fooled everyone and went to 8mm) and .416. The .30 is by far the most popular, but I've been using a 7mm, which is called the Tomahawk, for ten years, and it impresses the hell out of me. My friend Wayne Van Zwoll, a person of the highest literary and moral worth, has used the .338 cartridge, the Galaxy, and likes it a bunch. He's killed an elk and a bear with it, using factory ammo, and reports that it has very little kick in light of what it will do. But I digress; this is about the Tomahawk.
The factory ballistics for the Tomahawk list a 140-grain bullet at 3,380 and a 160-grain at 3,152. It's the ballistic twin of the 7mm Weatherby magnum, but in a much shorter case. Just as I prefer 160-grain bullets in the Weatherby, I favor them in the Tomahawk. They destroy less meat, buck the wind better, and penetrate better. My handloads give 160-grain Nosler Partitions exactly 3,000 fps, and to date, nothing has complained about the missing 152 fps.
Lazz brass never seems to wear out. It is a little bit thicker at the base and web than other short magnums, and the cases just seem to go on forever. I've been reloading the same batch of 50 since I first got the gun. (Lazz brass is now made by Hornady, so my guess is that the new stuff is even a bit better than what I have.)
Lazzeroni rifles are not cheap, even by the standards of this blog. Lazz spares no expense in building them, even down to such refinements as titanium firing pins. But there's no reason you can't have a rifle built for his cartridges, or rebarreled for them. You can either get factory ammo, which fairly howls along, or get the brass and dies and handload, which gives you even more options.
A tip: I've found that regular large rifle primers work better in the short cartridges than magnum primers do. What with the short powder column, you don't need so big or long-lasting a flame to set it off.