If you want the original "FBI Load," (the one they adopted in 1933), then get Buffalo Bore "Outdoorsman," Catalog Number 20H/20.

That load, made by the various manufacturers back in the day, was safe in the FBI's Colt Police Positives, and S&W said it was approved for the 2 inch M&P revolver, which has a weaker cylinder than the J frame as the locking notches are cut into the thinnest part of the cylinder wall over the charge holes.

Later, Evaluator's Ltd. tested the 38/44 load with the 4 inch Model 15, and found that it was fine for limited use in practice and qualification and for duty or combat use with most practice being done with standard loads.

Buffalo Bore's version will get you an honest 1,150 fps in a 4 inch Model 15 and around 1,000 fps in the 1 7/8 inch J frames. And, it is safe for use in those revolvers.