Your load is a full 300 fps faster than mine, in Tanzania 2020 i took a 400 H&H with 400gr Swift A Frames as my light plains game rifle, the 577 double done the heavy lifting on Hippo and Cape Buffalo bulls on the ground at 18 and 26 yards, knew going in i would be Leopard hunting with the 400, also knew it was slow and the A frame was tough.
Took a flat file and removed the small lead tip, hit the now small flat meplat with a center punch, drilled 1/4" deep holes with an eighth inch drill bit making some homemade hollow point Leopard bullets, they landed three inches high at 100 yards with the originals, picked out a black spot at the rear edge of my cats shoulder dead broadside 77 yards from the blind, he landed with a dead thug, my young 28 year old PH was so happy he hollered " i love you Sir" lol, you see one of the trackers on this trip had already left camp and returned from getting antibiotic shots from a Leopard bite right before Wife and i got there.
Last hunter before us wounded a cat, the PH had to place the barrel of his 450 Rigby against the cat and blast him off the tracker, what a damn dangerous mess poor shooting can be, my slow rifle and load accounted for plains game from 77 to 287 yards, it's all very easy shooting from sticks or blind if you practice and know your drops.
I think your setup will be perfect for Leopard and any other plains game you may encounter, have fun, shoot straight and let those lifetime memories that will never leave you march right in and settle in your head.
