Am looking at the discontinued Ruger pc9 and Marlin Camp carbines. Just want something to plink my pistol bullets in. With Marlin having the micro groove barrel wondering if that would work in the 9mm or the 45? Also heard that the 40 mm Ruger carbine got lousy groups like 10 in at 100 yds. Does anyone have any experience with these guns? Sure would like to know. Any info would be appreciated thanks Phil