A game guy used buffalobore.com's 45 Colt load:
260 grain hp at 1450 fps.
I like this round. Powerful, but, doesn't kick like the 325's or bigger bullets.
Advantage would be you could use that in your S&W, and it would feel like a 22lr, compared to the absurd, high pressure stuff most factory ammo is for that gun. And, you might need your barrel replaced at 1200 rounds, or have a cut top strap.
Your only real way to get a backup gun that's more powerful would be a .480 Alaskan, or anything with a bigger bore, and heavier bullet. .500 caliber bullet, or .510, with a 450 grain Hawk hollowpoint might work.
.500 JRH, based on a Ruger would be my choice. 440 grain flat points. Nice, light, single action.
Or, if you want a REAL big bore pistol:
Or, an FA in .475 Linebaugh. 400 grain XTP factory load from Hornady works well, and, at 1350 fps, it's easy to shoot.
You could always sell that pretender, and get either a 500 max, or, a S&W 500...
525 Grain bullets, at 1350 fps...
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