The 200 gr FN is heavier than optimum weight for 357 mag, whether rifle or revolver . This in my personal opinion based on many kills by myself, my wife and as reported by customers over the 35 years I've been making molds. I consider a 180 gran as optimum, because, with both weights loaded to full potential,the 180 gr creats a much larger wound than 200 grains, due to higher velocity potential.
As for penetration concerns. The deepest I've been able track a 180 gr FN was through an elk shot quartering from the rear of the ribs, exiting west of thr throat and east of the shoulder muscles. As it exited, after 30 inches of penetration it was still ripping a one inch diameter wound. This from a Marlin carbine which starts it at 1800 fps. The elk walked about 30 yards and folded, dead as a rock by time I got there, any as I recall I shot from about 75 yards.
The one inch exit wound indicates that the bullet was still moving faster than a revolver will push a 200 grain, which is in the vicenity of 1000 fps. At that speed the wound diameter will be less than an inch.
In 34 years of production no one has reported recovering one from game and there have been thousands of deer, hogs, bear and elk taken with the 180 gr. I would personally feel completely comfortable carrying the 357 carbine in big bear country as a defense gun when loaded with the 180 FN. I'd be less comfortable with a 200 gr in rifle or revolver, and with either firearm more comfortable with a 160 gr FN than a 200 grain.
I DEFINATELY would not use any jacketed bullet, nor any SWC for hunting, whether I made the mold or some other company, and keep in mind that I can make a variety of SWC styles as easily as I can cut the LBT designs. I've discussed the issue of meplat doing all the work with a hard cast bullet, many times on this forum, and in great technical detail in my Book Jacketed Performance with Cast Bullets. I have proven without question by anyone who does a little testing that the meplate along does all the work in live targets,
I suppose that if all the animals my wife and I have killed with the 357 Marlin Carbine were in the box of a full size pickup it would be close to level full. Almost all of them dropped in their tracks but a very few walked a few steps, slowly, Not one has run away.
To come closeat to that performance with a revolver on deer, most hogs, and smaller game, I'd recommend the 160 gr FN, with gas check, loaded hot. (The gas check increases velocity a good 50 fps, and LBT bullet lube adds about the same compared to any other cast bullet lube that I know of. This with equal ressure loads..