Is it necessary to break in barrels with a rimfire?

A barrel break-in is a crucial procedure to improve accuracy in a centerfire rifle. Is it required for a rimfire? It depends …The Basics Of Rimfire Barrel Break-In:Much depends on the rimfire cartridge being shot.Cartridges that shoot lead bullets, such as .22LR do not require a barrel break-in.Jacketed cartridges, such as .22 WMR do require barrel break-in the same as a centerfire.Also, it depends on if the rifle’s barrel is rough or has been hand lapped.This article is an excerpt from Rimfire Revolution: A Complete Guide to Modern .22 Rifles, available at GunDigestStore.com.Breaking in a rifle barrel through a routine of shooting, then cleaning, then shooting some more is either a required step for a precision rimfire rifle system or not necessary at all, depending with whom you talk.The more accurate answer to rimfire barrel break-in is, “it depends. First, consider the caliber. A.22LR that shoots lead bullets may need a different process from a.17 HMR,.22 WMR, or.22 WMR which shoots jacketed bullets. Lilja Rifles, Inc., a veteran in precision shooting, states that rimfire rifle barrels are different than centerfire barrels in that they need minimal cleaning and require no break-in procedure. They then state that the.22 WMR (or.17 HMR) cartridges are rimfires but they fire a jacketed round and require centerfire cleaning. Break-in instructions also apply. “Lilja barrels, as well as Shilen, Muller and Bartlein premium makers, are hand-lapping to a mirror polish. This means that they remove any tooling marks from the bore during barrel-making. Factory barrels are not like this. Borescopes can be used to see the smallest nicks and ridges in many factory barrels. You can smoothen those imperfections by shooting lead.22LRs down the bore. The imperfections will fill in with lead and grease, which makes the bore more lubricated and allows for better groups. Factory rimfires shoot better after hundreds of rounds, which is why many rimfire shooters are allergic to cleaning their bores. There are some downsides to a dirty barrel. A factory barrel or rough barrel can be broken down by using it a lot, while a hand-lapped barrel doesn’t require this. A premium hand-lapped barrel can be kept clean for its longevity and accuracy. It takes only half a box of ammunition to “re-foul” it. In both cases, it is not as necessary to shoot, clean, shoot, clean using some prescribed protocol as it is for barrels that send copper-jacketed bullets downrange.Editor’s Note:This article is an excerpt from Rimfire Revolution: A Complete Guide to Modern .22 Rifles, available at GunDigestStore.com.More Rimfire Info:NEXT STEP: Download Your Free Storm Tactical Printable Target Pack 62 Printable MOA Targets with DOT Drills – Rifle Range in YARDS This impressive target pack from our friends at Storm Tactical contains 62 printable targets for rifle and handgun range use. Target grids and bullseye sizes can be found in MOA. Perfect for long-range shooting! Get free targets