More than .45acp....
I have been thinking of adding a "more than 45 acp power" semi auto for some time. Mostly due to the fact that I would like an alternative to my revolvers when it comes to a higher power round when I feel the need.
I have tried to simplify and thin the heard as much as possible for economy of scale thus adding another caliber is not something I do trivially while I have plenty of 357 around hence the appeal.
Simple choice, at first....go with the .357 as caliber of choice, or buy something new.
The sad fact is that magnum autopistols are a niche market, and other than "orphan" (discontinued) guns your choices are very limited. The Coonan is back in production, I hope it stays, but only time will tell. The Desert Eagle is in production. The LAR Grizzly, Auto Mag, and apparently the Wildey are all "orphans".
The currently available .357s are the Coonan and the Desert Eagle. They are quite different beasts. People have remarked on how big the Coonan is, but its the
smallest of the magnum class autopistols.
The Coonan is a little bit bigger and heavier than a regular Govt Model 1911A1. The Desert Eagle is much larger and heavier, and needs to be fed only a certain kind of ammo (NO LEAD BULLETS). The Coonan, being recoil operated, doesn't have this restriction.
The 10mm is available in different "beefed up" versions of service autos. Loaded to its potential, its powerful enough to be in the bottom end of the real "magnum" class.
Its a matter of what you want to do with it. If you want something "more" that's still close to reasonably sized for carry, one of the 10mms fits better.
Other than the Desert Eagle, the big bore magnum autos are all "orphans" as you put it. Shame, really.
Shooting big bore magnum loads from an autoloader is a much different experience than shooting them from a revolver. Its a
very different feel. And the further away you get from the Browing tilt barrel in a slide designs, the more different it is.
The Coonan and the Grizzly, both being derivatives of the 1911 style can be very accurate. The Auto Mag, Desert Eagle, and Wildey can be phenomenally accurate. But these are all far from the "service/duty auto" class in size and weight.
To make the most of what you already have (.357) go with the Coonan, and live with the sticker shock. The Coonan also handles .38s with a change of springs. If you want something as close, or still in the duty gun size class, the 10mm does that, but means another caliber.
Of course, if you reload, that helps on the cost, except when you need to tool up for another caliber.