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Bart B. · August 26, 2012, 08:20 AM

Barrel life numbers depends on one thing; when the owner notices accuracy dropping off to an unacceptable level.

When the .243 Win was first used in high power match rifle competition, David Tubb and others shooting top scores with it got about 1400 rounds down range before they noticed accuracy dropping off too much. Others who didn't shoot good scores claimed 3000 to 4000 rounds. Go figure....

Barrel life tracks close to the following; 1 grain of powder for each square millimeter of bore cross sectional area gets about 3000 rounds of barrel life shooting 1/4 MOA at 100 yards. At 1.4 grains per square millimeter, barrel life's cut in half; 1500 rounds Double that amount of powder and barrel life gets cut to 1/4th as many rounds. Benchresters shooting 22 and 24 caliber bullets at short range from PPC cases typically rebarrel around 3000 rounds. Sierra Bullet's 30 caliber test barrels chambered for the .308 Win. are also replaced at around 3000 rounds; their 1/4 MOA groups with match bullets start to open up. These cartridges are all burning about 1 grain of powder for each square millimeter of bore area.

If you and your stuff (rifle and ammo) start out with 1/2 MOA at a hundred, you may get twice as many rounds. If it's 1 MOA at 100, you may get 3 to 4 times as many rounds. For example, folks shooting the .308 Win. or 7.62 NATO in Palma rifles producing the best scores rebarrel at around 3000 rounds. Same ammo in a service rifle barrel and it'll last 10,000 rounds with the accuracy it gets.

August 26, 2012, 08:20 AM	#9
Bart B. Senior Member Join Date: February 15, 2009 Posts: 8,927	Barrel life numbers depends on one thing; when the owner notices accuracy dropping off to an unacceptable level. When the .243 Win was first used in high power match rifle competition, David Tubb and others shooting top scores with it got about 1400 rounds down range before they noticed accuracy dropping off too much. Others who didn't shoot good scores claimed 3000 to 4000 rounds. Go figure.... Barrel life tracks close to the following; 1 grain of powder for each square millimeter of bore cross sectional area gets about 3000 rounds of barrel life shooting 1/4 MOA at 100 yards. At 1.4 grains per square millimeter, barrel life's cut in half; 1500 rounds Double that amount of powder and barrel life gets cut to 1/4th as many rounds. Benchresters shooting 22 and 24 caliber bullets at short range from PPC cases typically rebarrel around 3000 rounds. Sierra Bullet's 30 caliber test barrels chambered for the .308 Win. are also replaced at around 3000 rounds; their 1/4 MOA groups with match bullets start to open up. These cartridges are all burning about 1 grain of powder for each square millimeter of bore area. If you and your stuff (rifle and ammo) start out with 1/2 MOA at a hundred, you may get twice as many rounds. If it's 1 MOA at 100, you may get 3 to 4 times as many rounds. For example, folks shooting the .308 Win. or 7.62 NATO in Palma rifles producing the best scores rebarrel at around 3000 rounds. Same ammo in a service rifle barrel and it'll last 10,000 rounds with the accuracy it gets. Last edited by Bart B.; August 26, 2012 at 08:26 AM.