alright as has already been pointed out, both x39 and x54 are capable of taking deer, the only question is do you need to be able to take them past 150 yards? if so then the AK will require a lot more experience behind the trigger as x39 loses a great deal of energy at range while x54 retains it over distance.
you will need to get a decent pattern of where your gun hits with hunting ammo. surplus FMJ ammo is going to hit differently than wolf FMJ and that is going to hit differently than hornady soft points or polymer tips. hitting high with mosins is normal due to the 300 meter battle zeros they gave them so you will need to aim quite low between 50 yards and 200. I would recommend seeing how you are able to do with the AK and I would use the more expensive hunting ammo to get it zeroed as that will give you a more realistic idea of where it will hit while hunting. if you are able to get better accuracy out of the AK then it may be your better option, accuracy kills more deer than firepower. just be sure to pass on any shots that are too far away to make a clean kill, which will probably be anything past your abilities with iron sights.
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