Bill,
I think your set-up is plenty good. If you take good broadside to slightly quartering away shots, you should have no problem. I shot a Mathews Z7 at 70# with Carbon Express Maxima Hunter arrows and 100 grain Shuttle T-Lock broadheads when I went last year. My total arrow weight was in the 410 grain range. I took warthog, kudu, gemsbuck, blue wildebeest, blesbok, impala, zebra and eland with that setup. I had an exit hole on every animal I took except for the eland.
Remember, African animals are tough, but if you put an arrow in the right spot, they go down in a hurry. Study suggested shot placement photos and memorize them. If you put an arrow in this area, they will go down.
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