I have a K31 which throws flyers , then shoots really well after 10-15 rounds down the tube.Not a hot barrel issue as I can set the rifle aside for 1/2 hour then first shot is a flyer, then settles down. Clean rifle and it's 10 shots or so before it settles down??? Any rationale reason for this? I have another, much more worn K31, shoots nice groups from the gitgo, so I don't think it's me.