Ron is right. You don't want to go hunting when you are 5 inches high at 50. Hell that is not even good for a 50 yard shot. If you fail to compensate, and you pull the shot 2 inches high, you will be 7 inches high, bad deal.
The round ball is a great deer killer. Put that bad boy in the lungs and the deer will die. I have killed 7 deer and 6 wild boar with the .490 patched round ball and the TC Hawken and none of them made it more than 50 yards. Great blood trail, not that you need it on a 35 yard tracking job.
Farthest shot I made with black powder was 80 yards, I would not take a shot at over 100, the round ball loses energy fast.
If it were feasible I would overnight ship you a dozen .490 round balls, but since it is New Years Eve that is not feasible considering your tight schedule. You might be able to sight that thing in with 5 shots, go ahead and give it a try. This is one great thing about the TC Hawken is those great adjustable sights. Go ahead and give it a few clicks in each direction and try a few new shots. I only take three shots into the woods with me anyway.