The Ruger 77 Target Varmint .204 Ruger w/a Leo 6-18 X AO scope has become my favorite center fire prairie dog rifle. One half inch 100 Yd groups are common with both the 32 and 39 Gr bullet reloads. I live in prairie dog and over the years have tryed out the 22 Hornet, 221 Fireball , 222 Rem, 223 Rem, 22-250, 220 Swift , 17 Fireball, 17 Rem ,and some larger bore rifles. For any one comming out to shoot prairie dogs ,one can get a lot of shooting if the have a 17 HMR, 17 Fireball and 204 Ruger rifles with them.