Shot today the latest batches of loads for practice and PD. Used the Berry's 124g. plated HP for the former and the XTP 124 for the latter.
The Berry HPs grouped almost as well as the XTPs, finally; I guess I was loading them to too-high velocities. This batch topped at c. 1230FPS (at 10'), driven by 7.6g. of Accurate5. Started at 7g., didn't see a trend in group sizes, and all loads cycled 100%. Will load probably 7.3g. 'till I run out of #5.
The XTPs were driven by 10.5 to 10.8g. of Accurate7, producing 10-foot velocities of 1350 - 1387FPS from my 4.5" barrel. If I had to choose one of those, it'd be 10.5g. at 1350FPS.
I finally have enough nickeled cases to shoot nothing but, and I like them; they seem to attract less debris from the Hornady One-Shot lube I use on them and do NOT wipe off...just lazy, I guess.
For a few days I've had a vague feeling that my 357 reloads of all kinds ought to be producing smaller groups, but tonite I reviewed data on my .40-cal. 23. Overall, the 357's groups are maybe a little
smaller, not larger. ...

... (It was the much-longer model 35 that was producing the smaller groups.)
From the 80 different 357SIG loads I've tested, I've now selected a halfdozen loads to reevaluate using a new CED chrono that should arrive this coming week. FedEx had crushed the one that arrived Friday and it doesn't work. Graf & Son rushed a replacement Friday the 28th; they're good people.