Wyoming and Colorado both have good public land for this. Also, many land owners would let you pay a trespassing fee that would gain you access to grade A antelope ground. Many ranchers see them like praire dogs, a nuisance and an animal they don't mind you killing. Plus you're bowhunters so they won't see you as much of a threat when it comes to accidentally shooting livestock. Also, you have a kid which helps. Look around Carr, Colorado. Maybe the Pawnee grasslands. I do know of very good public land in the Custer national park in south east Montana. Near camp crook South Dakota. Easy to find info online for those areas.