strykervet: actually, IIRC the titanium cylinder failures in the 340 PD are typically linked to overenthusiastic cleaning of the chambers and thereby removing the plating therein--or something like that. At any rate, although there have been failures in M&P 340 cylinders as well (SS), they are much less likely to fail. Lower pressure rounds are not required, except for one's sanity and hand.
I've found that a 158-gr. LSWC-HP round running at about 915 fps from these short barrels is a max round--and that these do not strip out and lead the barrel excessively. Those appear to be rounds running at about 24,000 or so PSI, and I build them in 357 cases; they can be built in .38 Special cases as well 'though it's not a good idea....
Jim H.
I get 1302 fps from my 180 grain handloads from a 2.3" SP101. Heavier the bullet, the less barrel length has an affect on .357. I don't carry those 180s for defense, though, carry a 140 Speer over 17 grains 2400 at 1340 fps from same SP101. The 125 grain .357 stuff is pretty pathetic from a short barrel.
