Unless you do something to screw up the barrel you won't ware it out in your lifetime. The rifle should be cleaned once, when new to get the factory gunk out of it and then again only if you notice your accuracy diminishing, in which case you are getting a build up of lead alloy. Crossman Premiers are notorious for lead build up but usually only in high powered air rifles. DO NOT use Hoppes No. 9 or any other solvent made to clean firearms. Even if you think you have all the solvent out of the barrel you might not and a loud bang will occur, possibly damaging the rifle. Both Beeman and RWS and others, possibly make products specifically designed for air rifles.And you can pick up a .177 rod at Wal-Mart, if you don't already have one for about$5.00. While some airgunners don't use a brass brush, I have and will continue to due so: just don't over use it. Personally I have never seen a brass brush hard enough to scratch even soft steel.Although I will confess, I have used Goo Gone to clean out the factory gunk when I rifle is new. Feel free to ask more questions, we'll trip over ourselves trying to get you an answer.