October 19th 2023RifleBarrels.com, the website of barrel-maker Dan Lilja, has a great FAQ page with a wealth useful information. You’ll find answers for many frequently asked questions on the Lilja FAQ Page. Dan’s FAQ, for example, addresses the question of barrel longevity. Dan examines factors that influence barrel longevity and makes some predictions for barrel lifespan based on calibers, chamberings, and intended uses. NOTE: This article received a lot of attention when it was published. Dan warns that “Predicting the barrel life is a complex, highly variable topic — there is no simple answer.” The signs of a barrel that is losing accuracy are increased copper fouling and a lengthened throat depth. How many rounds can I expect my barrel to last?
A: This is a great question that our customers ask often. There is no simple answer. I believe there are two types of barrel life. Most of us refer to the accurate barrel life when we ask this question. There is also absolute barrel lifetime. This is the point at which a barrel can no longer stabilize a shot and accuracy is erratic. When asking this question, benchrest shooters and to a lesser degree other target shooters only consider accurate barrel life. For benchrest shooters who compete in matches where the group size is used as a measure of precision, accuracy means everything. To a score shooter, however, accuracy is less important when firing at a bull or target that is larger than a rifle’s potential group size. For a prairie dog hunter, the difference in accuracy between a rifle that is.25 MOA and one that is.5MOA may not be noticed in the field. Heat is the biggest enemy of barrel life. The throat area of a barrel is eroded and loses its accuracy. The crown can also be worn down by cleaning. Heat accelerates the throat erosion. If you fire a fast varmint cartridge without letting it cool, a barrel can be destroyed in a few hundred shots. A cartridge that uses less powder will last a lot longer. Increasing the bore size of a powder volume can also help. The.308 Winchester is based on a larger case than the.243 Winchester. Stainless steel barrels last longer than chrome moly barrels. This is because stainless steel resists heat erosion better than chrome-moly. Barrel life guidelines by caliber and cartridge type
As a rough guideline, I would say you can expect a barrel life of between 3000 and 4000 accurate rounds with cartridges in the.222 Remington caliber. Varmint accuracy should last much longer than that. For medium-size cartridges such as the.308 Winchester and 7×57, or even the 25-06, 2000-3000 accurate rounds is reasonable. Hot.224 caliber cartridges will not perform as well and you can expect 1000-2500 accurate rounds. Magnum hunting rounds can shoot between 1500 and 3000 accurate rounds. The larger 30-378 Weatherby models will not perform as well and are closer to the 1500 round figure. These figures are based on stainless steel barrels. For chrome-moly, I would reduce the numbers by about 20%. I can’t predict a number for the.17 and 50 calibers because they are their own rules. The 22 long rifle barrels (.22LR) are the most durable and can last 5000-10,000 rounds of accurate ammunition. One of our Anschutz barrels has been shot 200,000 times and the shooter is a small-bore competitor. He reported that the barrel had just stopped shooting. Remember that predicting barrel lifespan is a complex and highly variable topic. You can be the best judge for your barrel. Increased copper fouling, increased throat depth, and decreased precision are signs of accurate barrel life waning.
I thought it would be interesting to share a few of the exceptional Aggregates I’ve shot with 6PPC Benchrest rifles that have barrels that have thousands of rounds in them. I know benchrest competitors who would never fire barrels that had more than 1500 rounds in them at registered benchrest matches.I shot my smallest ever 100-yard 5-shot aggregate in 1992 at a benchrest registered match in Lewiston Idaho. It was a.1558″ aggregate fired in the Heavy Varmint category. This barrel had 2100 rounds in it at the time. Another good aggregate was fired during the Light Varmint 200-yard event at the 1997 NBRSA Nationals held in Phoenix, Arizona. I placed second with a 6PPC that had 2700 rounds in it at the time. After that match, I retired this barrel because it was starting to copper-foul a lot. But accuracy was still very good.
Tags: Benchrest, Copper fouling (Rifling), Dan Lilja. NBRSA. PPC.
