I've got a Yugo capture K98 mauser that you can barely see where the lands start from the chamber end (I'm guessing due to a lot of rounds fired through it) and when I do my part is around 2 1/2" to 3 1/2" groups at 100 yards with Yugo surplus ammo. The muzzle on this one is perfect. I was told that the muzzle end is the most important part of the rifle's accuracy, but I could be wrong. All the shots being done with the iron sights of course! I would imagine if I scoped it, it would probably shoot at least 1 1/2" at 100 yards!
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
How many shots to wear out a Rifle Barrel ?
- Thread starter TX Hunter
- Start date
troopcom mentions:
The four 7.62 NATO barrels I wore out in Garands all had enough metal rubbed off their last half inch or so of the bore and groove diameters that no copper wash was visble there when they were replaced. That wash ended about a half inch back from the muzzle, but accuracy was excellent. When new, those barrels shot under 4 inches at 600 yards but after about 5000 rounds when they opened up to under 5 or 6 inches, they got replaced. It was interesting watching the copper wash go all the way to the muzzle when they were new, then cleaning the bore every 30 to 60 shots with a solid steel cleaning rod began wearing away the tops of the lands and middle part of the grooves. Didn't notice any significant accuracy drop off until about 3000 to 4000 rounds but at about 5000 rounds it was readily noticed; that's when the bore erosion gauge read "5" a new barrel was put in.
When Garands in .30-06 were used in competition, they got replaced at about 4000 rounds; that's when the same bore erosion gauge would read "5" and accuracy had dropped off a little bit.
I think the reason great accuracy was still possible with a barrel with a bit larger bore and groove diameter at the muzzle's last half inch or so was it was quite constant for a few dozen shots fired in one day.
As soon as the origin of the rifling (leade) is eroded away and roughened up enough by powder burning at high pressure, bullets fired will have enough jacket material scraped off unevenly around them unbalancing them such that when they leave the muzzle, they jump a bit off the bore axis depending on where their heavy side is. As all bullets enter the origin of the rifling at slightly different angles, that's gonna determing what part of them gets jacket material removed more than some other place. And those unbalanced bullets don't land on target as close together as the best balanced ones do.
As long as the muzzle's not got a bad gouge at the edge of the rifling at its face, they can be worn back a ways from cleaning from the barrel's front end and still shoot very, very accurate.I was told that the muzzle end is the most important part of the rifle's accuracy, but I could be wrong.
The four 7.62 NATO barrels I wore out in Garands all had enough metal rubbed off their last half inch or so of the bore and groove diameters that no copper wash was visble there when they were replaced. That wash ended about a half inch back from the muzzle, but accuracy was excellent. When new, those barrels shot under 4 inches at 600 yards but after about 5000 rounds when they opened up to under 5 or 6 inches, they got replaced. It was interesting watching the copper wash go all the way to the muzzle when they were new, then cleaning the bore every 30 to 60 shots with a solid steel cleaning rod began wearing away the tops of the lands and middle part of the grooves. Didn't notice any significant accuracy drop off until about 3000 to 4000 rounds but at about 5000 rounds it was readily noticed; that's when the bore erosion gauge read "5" a new barrel was put in.
When Garands in .30-06 were used in competition, they got replaced at about 4000 rounds; that's when the same bore erosion gauge would read "5" and accuracy had dropped off a little bit.
I think the reason great accuracy was still possible with a barrel with a bit larger bore and groove diameter at the muzzle's last half inch or so was it was quite constant for a few dozen shots fired in one day.
As soon as the origin of the rifling (leade) is eroded away and roughened up enough by powder burning at high pressure, bullets fired will have enough jacket material scraped off unevenly around them unbalancing them such that when they leave the muzzle, they jump a bit off the bore axis depending on where their heavy side is. As all bullets enter the origin of the rifling at slightly different angles, that's gonna determing what part of them gets jacket material removed more than some other place. And those unbalanced bullets don't land on target as close together as the best balanced ones do.
Ive got an Old Fin M39 with a badly worn barrel, very faint Rifeling at the Throat, Poor Crown, Still Visible Rifeling. Its still pretty accurate, but takes alot of patches after a shooting session. I figure the rough bore captures more fowling than a smoother newer bore would.
That Rifle must have been shot thousands of times, probably at the range, in the War, maby both.
That Rifle must have been shot thousands of times, probably at the range, in the War, maby both.