New .22WMR 597. Worked perfectly first 200 rounds after I loosened bolt guide rails set screws. Now rifle fires first chambered round, ejects empty and chambers new round. The hammer follows the new round to the chamber and indents cartridge almost to the point of firing it. The rifle now has a unfired round in the chamber, hammer is uncocked, magazine partially loaded. What is wrong with this rifle? Please help! Oh yeah, if you can get your finger off of the trigger real fast after the shot it functions normally. Thanks for any help with this problem.