Sounds like a fun match.
CAUTION: The following post includes loading data beyond currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The High Road, nor the staff of THR assume any liability for any damage or injury resulting from use of this information.
There. That's taken care of, One good load for .357 shooting I use is---
162 gr. LSWC, WSP primers, 7.0 gr. Unique. This chronographs at 1144 fps from my brother's 6" bbl Taurus revolver. It is consistent and accurate, and not nearly so vigorous os many others. This load IS within limits in one manual, and not in another.
I also like the Hornady XTP 158 JHP with 14.5 gr. of 2400. It has a lot more sound and fury than the previous load, and should not be used as a steady diet in K-frame magnums. Should be fine in a Blackhawk, though.
One hint about consistently uniform holdovers--Keith wrote of having silver or gold lined inlaid in front sight of a couple of sixguns. I was happy with painting a line or two in the front sight serrations using "White Out" typing correction fluid. It is easy to clean out with solvent and a brush, for changing the aiming bars.
Good luck to your spouse in the contest. One caution, though, NB--Help with the hand loads, clean the revolver, shag brass, tote ammo, set up practice targets--Just DO NOT get into this game yourself. It is terrifically habit forming.
Best,
Johnny
oops--The caution msg was cut & pasted from an old text file--Had to come back and change the reference from The Firing Line to THR.