So I've goon from good to quite poor. White target on left was show with my CZ 457 w/ Lilja barrel and Timney trigger in KRG Bravo chassis. SK rifle Match at 50 yrds. Timid wind, 3-4 mph. Orange target is three weeks later with same set up. I suspected a dirty bore and so got to cleaning. Soaked the carbon ring and brushed it with nylon brush. Ran Rimfire Blend through the barrel. Set the action screws to 45 Lbs. Went out was at range at Markham and got the same results as the Orang target(left it in truck) Two Ranger Officers took turns and got same results. Didn't hold for wind, just straight on target. I am at a bit of a loss at what is going on? Cleaned the bolt, though didn't disassemble it. Cleaned all the usual places. Never been dropped or banged around. I am quite frustrated, and honestly don't know what is going on on and how to correct it.
Looking for advice and suggestions, thanks in advance.
regards,