No problem, we have dealt with this several times when customers have brought in straight ground venison. Our formula uses pork butt and ground chuck (or chuck steak / rst). Grind the pork and beef together through your fine plate. In a large tub mix the ground venison and ground pork/beef mix throughly together. Re-grind the total mixture once more through the fine plate and you will have an excellent burger.
    Note: Being a hand grinder you may have a mushing problem on the final grind, if so put the mix in the freezer and chill to the point where it's just starting to freeze and then make the final grind.

Dave