If your interested in a high velocity handgun cartridge, there is a discussion in converting a revolver to the 22-32 MAG cartridge in the book, "Sporting Firearms, A Designer's Notebook." I got my copy from Amazon.com Muzzle speeds were above 2000 fps, using a 7 1/2 inch barrel.
SF

That one may work, but so many of the attempts to get a bottleneck cartridge to work in a revolver have not.
Claims have been that a meticulously clean chamber prevents the setback/ cylinder binding issues.
I don't know, I have always wanted something of the sort, but the binding issues kept me from ever pushing the purchase button

I don't own a 22/32 FA, but I tested Bob Baker's FA Mdl. 97 in the cartidge 3 years ago at the NRA Whittington Center. It was very accurate @ 100 & 200 yds. and exhibited no set-back problems. It ran a 40 gr. Nosler BT @ 2250 fps @65* and 6500 ft. elevation. Bob tells me you can expect ~ 2150 fps from a 7 1/2" barrel and ~ 2050 from a 6". The .327 Federal cases require trimming .070" before loading.

I have a custom revolver chambered in 218 Mashburn Bee that I use for varmint hunting. It will shoot a 40 grain Sierra Blitz at 2200 fps.





A friend of mine has the Freedom Arms 22/32 FA and used it to harvest this Muntjac.

I have a Contender bbl. in 221 Fireball. I've shot a few groundhogs and a few prairie rats with it, but really haven't used it much. I really should take it out more, it shoots very well.

I have always wished to have a 6 shooter in 256 Win Mag.
I know there are issues with it when the velocity goes up.

I haven't tried this but I found this on youtube while searching for info on a different project. If these work then this would be a pretty cheap way to get some extreme velocity out of your .357 without having to do a custom job.

http://www.youtube.com/watch?v=rjTmXOjA5RU