There is a place near Arapahoe and Peoria in the Tech Center called Centennial Gun Store. I went in there over lunch the other day to look around. They have some AR stuff and mostly domestic guns (Smith, Springfield, Glock, Kahr). The range is something like 21 yards. The only ammo restriction is no steel core stuff or black powder stuff. You can shoot rifles on the range, and they even have an AR rifle to rent. $18 per hour for range and they recommend you call ahead for a spot, even during the week.
I haven't shot there or anything, and couldn't find another review. One thing I liked, was that they had a bunch of Comp-Tac Mtac holsters in stock, and even have the standard 1.5" black clips in stock as well.
I plan on shooting there over lunch someday, and will report back when I do. Anyone else ever been there? It has been so long since I've bought a gun, and I have so few guns, that I really couldn't tell you about their prices. I just assume all retail places are more than I want to pay.