Don't know about an elk load but I have been shooting a lot of power belts. I have an Optima, which the only difference, is your Pro is 2" longer. My Optima loves the 295g tip and hollow point. I am still using pellets and it likes 100g of 777. Can't afford to bang a lot of them at the range.

For the longer range you may need, look into the the platinums that power belt came out with. Good accuracy and they should stay together. Good luck with your hunt!