I have a Rock River upper 24" 1-12" twist flat top with the Wylde chamber . It is a great chuck and yote gun. Great accurey with my 55 gr V-Max load . The second shot has never been needed except for the 2 and 3 yote running to my call. I put a 6.5 x 20 Leupold Var X III on my gun (I had it) . If you build up a gun like I did , put a good light trigger in or have your worked on ,some stock triggers are HEAVY . Have fun busting yotes.