Re: 22LR Barrel Break in
Well, I signed up here, may as well get my first post out of the way...
No, no need for any breakin procedure but you may find that it will break in over time and shoot better a thousand rounds from now than it does when it's new.
Personally, I like to keep them clean. Maybe it's just a state of mind but all mine shoot better clean. Doesn't take much. Only way to know is experiment.
To the other poster, Remington rimfire ammo is pretty dirty as far as powder fouling goes but copper washed bullets aren't going to hurt anything.
Tony