If thats what you got then use them. But I would choose something a bit softer,why do you think you will be shooting to 450 meters? Do you expect to find the animal after its tumbled out of sight and you have to detour 2km around a face in order to find roughly where you think you last saw it,kind of?
Honestly I would sight it in with Norma Oryx and just buy some when you are in NZ.
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