17 caliber bores crap up pretty easily. The good news is that the 17hmr doesn't carry the powder charge of the 17 Remington, etc. You are firing copper jacketed bullets however. When accuracy falls off, clean it. Then use a good copper solvent to completely remove the fouling. With a bore guide and properly fitting equipment you only have to observe good cleaning techniques to preserve your bore. Then keep track of rounds fired. Keep careful track of accuracy, clean and as the bore fouls. Typically it will be so-so for a number of shots and then get good and stay there a long while. This will give you a good baseline on cleaning. The advice everyone has given is pretty similar. The roughness of each bore can vary so that each rifle is it's own entity. My Lilja barreled custom 17hmr bench gun has shown no tendency to copper foul at all while my Savage 93 sporter shows a bit after 500 rounds. You're going to have a ball while you learn your rifles tendencies. My best, Guy
