Don't have a .357 lever, but do have a pump (similar concept) in the form of an 18" IMI Timberwolf, so let me give you my thoughts.
1.
www.ballisticsbytheinch.com and other experiments have shown that the .357 mag, more than any other handgun round, and possibly more than any other rifle round either, for that matter, benefits tremendously from a longer barrel, relative to a handgun, with oddly, very little diminishment of the returns - in fact, bordering on magically-so. It's a real thumper from an 18+ or longer barrel, almost on a par with .30-30, when using the right powder such as L'il Gun. It is for this reason that I have this rifle but do not have any .357 mag handgun - not a fan of the latter. Go take a look at the claimed vels of the Buffalo Bore heavies from a rifle - unreal.
2. Reloading this round, like all straight-walled, is a relative joy, with good case life. I recommend reloading for it if you hadn't already planned to.
3. As mentioned, you can run .38 special in them, particularly if you adjust the COL to match .357 mag - the Timberwolf feeds them just fine, anyway, and the Marlins do too from what I read.
4. As far as the use / niche, I think the primary one - and the reason I kept mine, is self-defense instead the home and around the homestead, especially for a lady or teen. Very fast, handy, much lower ear damage in the event of use than a .357 handgun, and powerful enough to thump a wolf, cougar, bear, etc., attacking pets or livestock. Secondarily, particularly using .38 special, it's a decent "woods bumming" rifle (if one does that sort of thing), where you are really just out to enjoy a woods walk more than anything else, but have several smaller species in season, and don't know what you might come across - suppose there's a crossover of seasons on various game and non-game critters like rabbits, grouse, coyote, beaver, bobcat, fox, other furbearers & varmints. It won't completely destroy a grouse, but is enough gun for even a wolf / cougar size, in my view. Even in deer season, it's one choice, though wouldn't be mine, so I don't consider this a good use for it.
"You can get a a red dot mount for a M92" - and you get get regular scope mounts for the Rossi that replace the rear sight - but you need a LER scope with short length, or a dot sight - maybe we're referring to one and the same mount type.
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