Preheat the oven to 375 degrees F (190 degrees C).

Mix venison, stuffing mix, water, onion, 1/4 cup barbecue sauce, eggs, salt, and black pepper together in a large bowl until fully incorporated. Shape venison mixture into a loaf and place in a 9x13-inch baking dish. Spread remaining 1/4 cup barbecue sauce over the top of loaf.

Bake in the preheated oven until no longer pink in the center, about 1 hour. An instant-read thermometer inserted into the center should read at least 160 degrees F (70 degrees C).