Remember this thread? - https://www.thehighroad.org/index.php?threads/you-never-clean-a-22-rifle.894731/page-2#post-12052173 I have done several "myth busting" threads for Handloading & Reloading category of THR over the years with certain degree of success (List of myth busting threads in the linked post) - https://www.thehighroad.org/index.php?threads/myth-busting.876700/page-2#post-11678818 "Since there are many ... variables, some myth busting can be more difficult as these other variables must be reduced or eliminated first. So to conduct effective myth busting (And believable by THR peanut gallery), you would have to prove how you isolated the variable you are myth busting or confirming." I have wanted to do this myth busting of dirty vs clean 22LR barrel accuracy for some time but since barrel accuracy involves shooting variables (Construction of hard machine rest was put on hold due to cataract/glaucoma/technical issues ... Thankfully, cataract surgery with Vivity IOL implants went well), scoped 50 yard range tests were done on Lead Sled Solo stabilized with a roll of blue painter's tape. Factory Trigger Break-In - And since I am using factory stock 10/22 and T/CR22 with factory triggers (which BTW went from 7.5 lbs to 4.5 lbs for 10/22 after 3000 rounds and 6 lbs to 4 lbs for T/CR22 after 1000 rounds), I am hoping to correlate 10 shot groups captured with various ammunition from 10/22 and T/CR22 "real world ..." threads to determine whether accuracy improved or not between dirty vs clean barrel by comparing "relative" group size variations. In preparation for this myth busting, new 10/22 and T/CR22 barrels were intentionally not cleaned since out of the box (Not brushed with copper bore brush) and barrels were only mopped with Hoppes #9 and dry patched every 1000 rounds (Chamber and muzzle crown were cleaned as necessary along with magazines). Test Rifles - Here are 10/22 Collector #3 and T/CR22 used for testing (10/22 was free-floated with hard plastic shim under V block and back of receiver better stabilized with a strip of electrical tape. KSA 16.5" bull barrel will be installed on T/CR22 for the upcoming "Accurizing 22LR on the cheap" thread) 10/22 baseline 10 shot groups from Range Test #10 with 3500 round count - https://www.thehighroad.org/index.p...lector-3-break-in.859106/page-3#post-12110978 T/CR22 baseline 10 shot groups from Range Test #4 with 1500 round count - https://www.thehighroad.org/index.p...mmo-comparison-break-in.864241/#post-12110986 Cleaning of barrels - Both barrels were mopped with Hoppes #9 until dripping wet, soaked with ends plugged for 10 minutes and mopped again then soaked again for 10 more minutes before brushed twice with copper bore brush at end of cable (Brushed from chamber to muzzle) and dry patched with Viva paper towel (Keeping the "real world" theme). Even after 3500 rounds, 10/22 bore was fairly clean and shiny before the cleaning and not much came out of the barrel and dry patch was clean after several passes. After 1500 rounds, T/CR22 barrel was even cleaner and dry patch was clean after two passes. Rest of 10/22 and T/CR22 (along with magazines) were cleaned with Hoppes #9 and oiled with full synthetic motor oil as part of 1000 round routine cleaning.