I believe the area you are talking about is directly behind the queen valley dam.... Thick veg. sandy wash area that is pretty well shaded, and would be a great place for a summer game. The area is not listed on the USFS area of closure areas for shooting, therefore is legal to the best of my knowledge. I work for the USFS and would see any issues back in there, as there are lots of RS target shooters in the area. If you have any specific questions you can always call the Mesa Ranger district at
Address:
5140 E. Ingram St.
Mesa, Arizona 85205
Phone: (480) 610-3300
Fax: (480) 610-3346