Scott your own data shows the .357 10% + faster with the same bullet, recoil, yes it will and you will not like it. You probably won't notice it in a FTF put the bad guy down moment, but you will in practice. The .357 mag does get to it's full potential in longer barrels, but what it comes down to is that extra 90-100 fps, worth it, to me yes. I don't have a j frame in .357, but do in a 2 1/2" model 19, and it ain't bad with my boot grips even. I do own 2 j frames, a 649 in .38spl, stuffed with PMC Star something 125 grn hollow points, and my beloved 940 9mm, I carry 147 grn, black talons or 124 grn, Nyclads. This gun shoots well, but with 147's it is a tack driver. The 9mm does better in the short barrels than the .357 mag, since none have been made in a while, the comparisons between the 2 cartridges is not well covered. Feel free to Google Fu, and find one.
Any of you shooting the .357 mag in the J frame, do practice grabbing a small hand full of grip, and shooting targets at 7' to 7 yards, fast, like you mean it, sometimes 2 shots, other times 3 shots or till empty. The good thing about a J frame or a Ruger Sp101, Colt detective special, is even someone with small hands, can completely encircle it, for maximum grip torque. It will not stop the pain, but it will control the muzzle rise.