I only clean my brass occasionally with corncob media in a Rcbs vibrating cleaner. I do however polish the neck and shoulder with 0000 steel wool after ever firing. I also clean the inside of neck by running them onto a nylon barrel brush wrapped with the same steel wool. I have a variable speed motor set up with a drill chuck for cleaning the neck and it works great. I have tried the liquid ultrasonic cleaner and it does a good job cleaning inside and out but I don’t like dealing with wet brass! After cleaning necks inside and out you can anneal and come out with good looking brass. All this may or may not make the round more accurate but at least we have tried!!