I'll just say this......... you're shooting a very dangerous charge in that cheap ask production rifle barrel. You're lucky you haven't detonated that barrel, injuring yourself or a bystander, or worse.
I'm not saying that you didn't do that, nor am I saying you couldn't kill a bull with that bullet and charge at that distance. What I will say though as a long range shooter myself, 150 rounds of practice is no where near the minimum for a 500yd hunting shot.
Nobody in their right mind at CVA would give you that kind of bogus information. Sorry, I can't swallow that pill.
It requires a semi-custom, or a full custom rifle to safely shoot those charges and especially 327gr bullets or heavier.
Rifles such as the BP Xpress, Remington Ultimate and custom barreled rifles with breech plugs designed to take the pressures. Not a production barrel.
The only production rifle made today that the owner's manual will allow that heavy a charge, is the CVA Paramount rifle.
THOSE READING THIS POST AND INFORMATION......... PLEASE...... READ AND FOLLOW YOUR RIFLE'S OWNER'S MANUAL. DO NOT EXCEED THE CHARGES OR BULLET WEIGHTS LISTED IN THE MANUAL.
I like .45 but I just hunt deer. You'll do fine with a good .50. I've shot sub-MOA with 50s. Conicals is what makes it hard. Let us know how it all unfolds for you. Love the smokepole