I have been carrying the Buffalo Bore 158 gr. +P LSWCGCHP FBI load in my 340 M&P(s) for a number of years. I have chronographed them out of the 340 and got an honest 1000+ fps. I don't know about the composition of the bullet, but I've fired it through wet phone books and jugs of water. Not only was the penetration in both media within recommended FBI ranges, but the expansion was quite good. As stated above, however, it is a little stout in the alloy framed guns (although not as stout as most .357). I also keep my Model 60 loaded with the BB rounds.

In my 640, I prefer to carry magnum loads most of the time. For that gun, I like the Speer GDHP 135 gr. SB in .357. I trust the GDHP in just about every load in the calibers I've used; .38, .357, 9mm and .45 ACP.

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Dave Frost