O
Octopus
Guest
How long does a barrel last? Why are some calibers better than others? Why do some calibers burn out the barrel so fast?
These questions have a lot of answers. And, not all the answers agree. The 264 Win Mag is know as a “barrel burner”. Back in the early 60s there were many stories about barrels being “shot-out” with 500 or less rounds. On the other side there were stories about the 218 Bee and 222 with barrels that last forever. The following are the observations of several shooter that I have noted over many years of shooting.
These items result in shorter barrel life:
1. Burn more powder
2. Big case capacity with smaller diameter bullet
3. The heavier the bullet the faster the barrel washes out
4. Slower burning powders
5. Very high velocity (Usually goes along with the three items above)
6. Very high pressures
7. Rapid fire
8. Hot barrels
Today with the new powders and better quality barrels there are still issues about barrel life and “barrel burner cartages. How long a barrel last depends a lot on what you expect in the way of accuracy. If you happy with 1” @100 yards say 1.0 MOA, barrels last a long time. If you except “hunter accuracy about 3” @ 100 yards barrel life is not usually an issue. Hunting rifle barrels usually go bad from rust, i.e. the lack of cleaning and oiling. But, if you expect precision and demand the very best in the way of accuracy barrel life is a big issue.
My standards are: (@100 yards from stable bench 5 shot group aggs.)
Benchrest Competition Rifles 0.100
Benchrest Practice Rifles 0.200
Live Varmint Field Rifles 0.375
Long Range Hunting Rifles 0.500
Hunting Rifles 1.000
Muzzle Loaders 2.000
If a rifle (Barrel) does not meet these standards it will not find a home in my safe unless it is very old.
I have experienced some powders produce more heat into the barrel than others. For example the IMR powders heat the barrel more than the VV single base powders for the same velocity shot. I do not think this makes much difference overall.
Barrel life is very dependant on one’s accuracy requirement. I want my BR barrels to agg 0.100 or better but I tend to live with a larger agg. At 0.250 the barrel is done by all BR standards but would still be very acceptable for P dogs and other shooting sports. The differences in acceptable accuracy confuses the issue of barrel life reports.
I think there is a slight barrel life advantage shooting moly bullets. I also think the single point cut barrels last a little longer. How well the barrel is cleaned makes a big difference. Barrels that are kept clean seem to last longer. Some cleaning techniques can shorten barrel life. (I use only JP bore paste and Koil. I never use a metal brush or any harsh chemical cleaners in any of my BR barrels.) I bore scope my barrels very often. My cleaning procedures are based on the bore scope and what works for accuracy. There are chemical cleaning procedures that work fine and do not damage the barrels. As long as a workable cleaning procedure is use this should not have a significant impact on barrel life. Corrosion is a barrel killer.
My recorded experience for barrels with high numbers of shots is a follows:
222 1 barrel SST 1-14 Agg std 0.200 over 10,000 rounds and still shooting. Last forever I guess.
223 2 barrel SST 1-9 Agg std 0.250 about 2,000 rounds Failure throat and lands erosion
223 1 barrel CM 1-9 Agg std 0.250 about 2,000 rounds Failure throat and lands erosion
243 1 barrel CM 1-10 Agg std 0.750 Under 2,000 rounds Failure throat and lands erosion
25 BR 2 barrels SST 1-14 Agg std 0.250 about 1500 rounds Still shooting good
25-06 2 barrels SST 1-10 Agg std 0.375 2,000 to 2,500 rounds Failure throat and lands erosion
25-06 2 barrels SST 1-10 Agg std 0.375+ about 1,500 rounds Failure throat and lands erosion
30-06 2 barrels CM 1-10 Agg std 0.75 2,000 + rounds Failure corrosion pits near the muzzle. FL humidly.
308 1 barrel CM 1-10 Agg std 0.50+ 2,000 + rounds Failure throat and lands erosion.
6BR 2 barrel SST 1-14 Agg std 0.200 1,800 to 2,200 rounds Failure throat and lands erosion
6PPC 3 barrels SST 1-14 Agg std 0.200 2,000 to 2,200 rounds Failure throat and lands erosion
I would very much appreciate any knowledge and data that you can add to this subject.
To make the data more usable please always include the acceptable accuracy standard.
For the Agg I use the average of five shot groups. My experience is when the barrels start to go by throat erosion the bullet has to be set almost out of the case to reach the lands. Flyers start to show up. When there are pits in the barrel near the muzzle, usually caused by my poor care, the barrel will group for only three to five shots after cleaning then it opens ups. (As a point of reference the majority of all the rifle barrels I have inspected at gun shows with the bore scope had corrosion pits within five inches of the muzzle.)
My experiences with 22-250 and 25-06 are these calibers burn the barrels out of acceptable accuracy in about 2,000 rounds shooting a mix of 75% below velocity rounds and 25% maximum velocity rounds. The more powder you burn the shorter the barrel life. The barrel is usually best from 300-800 rounds down the tube.
A long range shooter using a 6.5 X 284 shooting slow burning powders and heavy VLD bullets may only get 700 to 1,000 rounds before the barrel’s accuracy drops off. Shooting rapid fire with a hot barrel does shorten barrel life. Shooting the same rifle and load slow where the barrel never gets hot will make the barrel last longer. 1.5 times or more longer. And there is a difference in powders. Some brands of powders burn barrel throats faster than others. If you take the 6.5 X 284 and shoot it for fun keeping the barrel cool using lighter bullets and only shot max velocity loads when needed the barrels will last over 2,000 rounds and still hold accuracy.
The 218 Bee and the 222 barrels will shoot almost forever. These barrels use little powder per shot and rarely get very warm. My friend Capt. Bob’s Ugly Gun with a 222 tight neck barrel has over 20,000 rounds down the tube that we have counted. And the gun and barrel was used when he got it. We think this is a Douglas barrel. It will still shoot aggs under 0.200 and sometimes better.
The Savage factory stainless steel 223 target barrels are quite good. I have seen two of these shoot below 0.500 all the time, below 0.375 some of the time and even better once and a while. These barrel seem to hold hunter accuracy 1” or better for 4,000 shots or more. But they usually open up over ½” after 2,000 rounds or so. For the price the Savage rifles and barrels are a good value.
Some shooters say barrels with single point cut rifling last longer, I think there is some truth to this.
It is important to understand that one must be shooting off a very stable bench, with a very stable 20-40 power scope, a tuned or custom rifle and a very light trigger to obtain the higher levels of accuracy. The bench and the rest gear must be benchrest quality. Most days at least 4 wind flags are needed for 100 yard shooting.
Calibers such as the 6.5X55 and 308 will often go over 4,000 rounds if the right powders and primes are used and if they are not loaded to hot. The 30 BR will go a few thousand rounds and still hold precision.
Calibers such as the 220 Swift, 243, 7 mm Rem Ultra Mag and 300 Win Mag will have shorter barrel life. These cases hold more powder and have smaller neck diameters, which focuses the heat in a smaller area, which makes it more intense. Kind of like the difference between a cigarette lighter flame and a miniature torch flame. They both have a flame but the torch is focus with higher temperature and more heat energy.
The first thing to go in a barrel is usually the throat area and the first few inches in front of the throat. This area can burn out fast. However, accuracy will often hold good when the throat area looks gone. A lot depends on your demand for accuracy. If you are happy with ½” groups barrels last longer.
As said by others smarter than I: “The process most responsible for eating away the steel in the throat is called ablation. Ablation is actual vaporization of the steel from heat as opposed to abrasion, which could be likened to "sandblasting". Much of the talk about sandblasting, abrasion, shoulder angles VS neck length (Turbulence Point Theory) etc is subject to question. Ablation is the result of hot gas impinging upon the steel surface for a sufficient time to melt some steel and carry it away. This is exacerbated by slow-burning powders coupled with large chambers and long barrels. Longer barrels hold the heat and the pressure longer.
Some powders burn hotter that others. Some knowledgeable people feel the "hotter" powder is lesser important than the duration of the event. Keep the heat concentrated on the steel's surface LONGER and you get more heat transfer and gasification of the steel.
These are know to be true:
• Using MORE powder, burning hotter over a LONGER period of time will always decrease barrel life.
• Rapid fire heats the barrel more and barrel burn is much faster.
• Keep your barrel cool and it last longer.
Most of the new calibers have came about not because they are need but because new calibers sell new guns. Look at the Ultra Mag series. Most of all the new calibers have an over bore powder capacity. That is the volume of the case is greater than is needed for the bore diameter. Accuracy does not sell rifles. Velocity sales rifles. When you loose sight of direction make up for it with speed.
Calibers with over bore capacity use lots more powder to gain only slightly more velocity. Recoil and muzzle blast noise go up faster than velocity.
With today’s new and better powders the 308 case has more capacity than needed for the 30 caliber bore. I have yet to see any of the 300 Mags, Ultra Mags or Short Mags better the tested and proven 308 at short or medium ranges. 200 fps never replaces bullet placement.
With today’s powders and premium bullets the Benchrest cases are making a come back. The 6 MM BR is a short version of the 243. It has and continues to win matches out to 1,000 yards. When you shoot a match lots of shots are fired. Recoil is a real issue as is barrel life. The 6 BR betters the 243 in regards to accuracy, recoil, barrel life and is very close in velocity.
For most calibers there is a wildcat version called the Ackley Improved, i.e. the 243 AI, the 25-06 AI and etc. These are the same as the original with the case shoulder mover forward, shorter neck and steeper neck angle. Usually the AI version will produce 200 fps more velocity. The AI versions with the steeper shoulder angles seem to have about the same or better barrel life. But accuracy is usually similar but sometimes the AI is better. With the AI the shorter neck lengths make neck tension more difficult to keep constant. If you load with the bullet into the lands this is not usually an issue.
Keeping the barrel clean and oiled is critical to barrel life. Lack of oil will kill a barrel over time. Barrels do not shoot good with rust and pits in the bore. Calibers with larger powder capacity seem to be more subject to rust and pitting damage. Barrels need to be cleaned from the chamber end and not the muzzle. Cleaning from the muzzle with out a muzzle guide will damage the bore and the muzzle.
These questions have a lot of answers. And, not all the answers agree. The 264 Win Mag is know as a “barrel burner”. Back in the early 60s there were many stories about barrels being “shot-out” with 500 or less rounds. On the other side there were stories about the 218 Bee and 222 with barrels that last forever. The following are the observations of several shooter that I have noted over many years of shooting.
These items result in shorter barrel life:
1. Burn more powder
2. Big case capacity with smaller diameter bullet
3. The heavier the bullet the faster the barrel washes out
4. Slower burning powders
5. Very high velocity (Usually goes along with the three items above)
6. Very high pressures
7. Rapid fire
8. Hot barrels
Today with the new powders and better quality barrels there are still issues about barrel life and “barrel burner cartages. How long a barrel last depends a lot on what you expect in the way of accuracy. If you happy with 1” @100 yards say 1.0 MOA, barrels last a long time. If you except “hunter accuracy about 3” @ 100 yards barrel life is not usually an issue. Hunting rifle barrels usually go bad from rust, i.e. the lack of cleaning and oiling. But, if you expect precision and demand the very best in the way of accuracy barrel life is a big issue.
My standards are: (@100 yards from stable bench 5 shot group aggs.)
Benchrest Competition Rifles 0.100
Benchrest Practice Rifles 0.200
Live Varmint Field Rifles 0.375
Long Range Hunting Rifles 0.500
Hunting Rifles 1.000
Muzzle Loaders 2.000
If a rifle (Barrel) does not meet these standards it will not find a home in my safe unless it is very old.
I have experienced some powders produce more heat into the barrel than others. For example the IMR powders heat the barrel more than the VV single base powders for the same velocity shot. I do not think this makes much difference overall.
Barrel life is very dependant on one’s accuracy requirement. I want my BR barrels to agg 0.100 or better but I tend to live with a larger agg. At 0.250 the barrel is done by all BR standards but would still be very acceptable for P dogs and other shooting sports. The differences in acceptable accuracy confuses the issue of barrel life reports.
I think there is a slight barrel life advantage shooting moly bullets. I also think the single point cut barrels last a little longer. How well the barrel is cleaned makes a big difference. Barrels that are kept clean seem to last longer. Some cleaning techniques can shorten barrel life. (I use only JP bore paste and Koil. I never use a metal brush or any harsh chemical cleaners in any of my BR barrels.) I bore scope my barrels very often. My cleaning procedures are based on the bore scope and what works for accuracy. There are chemical cleaning procedures that work fine and do not damage the barrels. As long as a workable cleaning procedure is use this should not have a significant impact on barrel life. Corrosion is a barrel killer.
My recorded experience for barrels with high numbers of shots is a follows:
222 1 barrel SST 1-14 Agg std 0.200 over 10,000 rounds and still shooting. Last forever I guess.
223 2 barrel SST 1-9 Agg std 0.250 about 2,000 rounds Failure throat and lands erosion
223 1 barrel CM 1-9 Agg std 0.250 about 2,000 rounds Failure throat and lands erosion
243 1 barrel CM 1-10 Agg std 0.750 Under 2,000 rounds Failure throat and lands erosion
25 BR 2 barrels SST 1-14 Agg std 0.250 about 1500 rounds Still shooting good
25-06 2 barrels SST 1-10 Agg std 0.375 2,000 to 2,500 rounds Failure throat and lands erosion
25-06 2 barrels SST 1-10 Agg std 0.375+ about 1,500 rounds Failure throat and lands erosion
30-06 2 barrels CM 1-10 Agg std 0.75 2,000 + rounds Failure corrosion pits near the muzzle. FL humidly.
308 1 barrel CM 1-10 Agg std 0.50+ 2,000 + rounds Failure throat and lands erosion.
6BR 2 barrel SST 1-14 Agg std 0.200 1,800 to 2,200 rounds Failure throat and lands erosion
6PPC 3 barrels SST 1-14 Agg std 0.200 2,000 to 2,200 rounds Failure throat and lands erosion
I would very much appreciate any knowledge and data that you can add to this subject.
To make the data more usable please always include the acceptable accuracy standard.
For the Agg I use the average of five shot groups. My experience is when the barrels start to go by throat erosion the bullet has to be set almost out of the case to reach the lands. Flyers start to show up. When there are pits in the barrel near the muzzle, usually caused by my poor care, the barrel will group for only three to five shots after cleaning then it opens ups. (As a point of reference the majority of all the rifle barrels I have inspected at gun shows with the bore scope had corrosion pits within five inches of the muzzle.)
My experiences with 22-250 and 25-06 are these calibers burn the barrels out of acceptable accuracy in about 2,000 rounds shooting a mix of 75% below velocity rounds and 25% maximum velocity rounds. The more powder you burn the shorter the barrel life. The barrel is usually best from 300-800 rounds down the tube.
A long range shooter using a 6.5 X 284 shooting slow burning powders and heavy VLD bullets may only get 700 to 1,000 rounds before the barrel’s accuracy drops off. Shooting rapid fire with a hot barrel does shorten barrel life. Shooting the same rifle and load slow where the barrel never gets hot will make the barrel last longer. 1.5 times or more longer. And there is a difference in powders. Some brands of powders burn barrel throats faster than others. If you take the 6.5 X 284 and shoot it for fun keeping the barrel cool using lighter bullets and only shot max velocity loads when needed the barrels will last over 2,000 rounds and still hold accuracy.
The 218 Bee and the 222 barrels will shoot almost forever. These barrels use little powder per shot and rarely get very warm. My friend Capt. Bob’s Ugly Gun with a 222 tight neck barrel has over 20,000 rounds down the tube that we have counted. And the gun and barrel was used when he got it. We think this is a Douglas barrel. It will still shoot aggs under 0.200 and sometimes better.
The Savage factory stainless steel 223 target barrels are quite good. I have seen two of these shoot below 0.500 all the time, below 0.375 some of the time and even better once and a while. These barrel seem to hold hunter accuracy 1” or better for 4,000 shots or more. But they usually open up over ½” after 2,000 rounds or so. For the price the Savage rifles and barrels are a good value.
Some shooters say barrels with single point cut rifling last longer, I think there is some truth to this.
It is important to understand that one must be shooting off a very stable bench, with a very stable 20-40 power scope, a tuned or custom rifle and a very light trigger to obtain the higher levels of accuracy. The bench and the rest gear must be benchrest quality. Most days at least 4 wind flags are needed for 100 yard shooting.
Calibers such as the 6.5X55 and 308 will often go over 4,000 rounds if the right powders and primes are used and if they are not loaded to hot. The 30 BR will go a few thousand rounds and still hold precision.
Calibers such as the 220 Swift, 243, 7 mm Rem Ultra Mag and 300 Win Mag will have shorter barrel life. These cases hold more powder and have smaller neck diameters, which focuses the heat in a smaller area, which makes it more intense. Kind of like the difference between a cigarette lighter flame and a miniature torch flame. They both have a flame but the torch is focus with higher temperature and more heat energy.
The first thing to go in a barrel is usually the throat area and the first few inches in front of the throat. This area can burn out fast. However, accuracy will often hold good when the throat area looks gone. A lot depends on your demand for accuracy. If you are happy with ½” groups barrels last longer.
As said by others smarter than I: “The process most responsible for eating away the steel in the throat is called ablation. Ablation is actual vaporization of the steel from heat as opposed to abrasion, which could be likened to "sandblasting". Much of the talk about sandblasting, abrasion, shoulder angles VS neck length (Turbulence Point Theory) etc is subject to question. Ablation is the result of hot gas impinging upon the steel surface for a sufficient time to melt some steel and carry it away. This is exacerbated by slow-burning powders coupled with large chambers and long barrels. Longer barrels hold the heat and the pressure longer.
Some powders burn hotter that others. Some knowledgeable people feel the "hotter" powder is lesser important than the duration of the event. Keep the heat concentrated on the steel's surface LONGER and you get more heat transfer and gasification of the steel.
These are know to be true:
• Using MORE powder, burning hotter over a LONGER period of time will always decrease barrel life.
• Rapid fire heats the barrel more and barrel burn is much faster.
• Keep your barrel cool and it last longer.
Most of the new calibers have came about not because they are need but because new calibers sell new guns. Look at the Ultra Mag series. Most of all the new calibers have an over bore powder capacity. That is the volume of the case is greater than is needed for the bore diameter. Accuracy does not sell rifles. Velocity sales rifles. When you loose sight of direction make up for it with speed.
Calibers with over bore capacity use lots more powder to gain only slightly more velocity. Recoil and muzzle blast noise go up faster than velocity.
With today’s new and better powders the 308 case has more capacity than needed for the 30 caliber bore. I have yet to see any of the 300 Mags, Ultra Mags or Short Mags better the tested and proven 308 at short or medium ranges. 200 fps never replaces bullet placement.
With today’s powders and premium bullets the Benchrest cases are making a come back. The 6 MM BR is a short version of the 243. It has and continues to win matches out to 1,000 yards. When you shoot a match lots of shots are fired. Recoil is a real issue as is barrel life. The 6 BR betters the 243 in regards to accuracy, recoil, barrel life and is very close in velocity.
For most calibers there is a wildcat version called the Ackley Improved, i.e. the 243 AI, the 25-06 AI and etc. These are the same as the original with the case shoulder mover forward, shorter neck and steeper neck angle. Usually the AI version will produce 200 fps more velocity. The AI versions with the steeper shoulder angles seem to have about the same or better barrel life. But accuracy is usually similar but sometimes the AI is better. With the AI the shorter neck lengths make neck tension more difficult to keep constant. If you load with the bullet into the lands this is not usually an issue.
Keeping the barrel clean and oiled is critical to barrel life. Lack of oil will kill a barrel over time. Barrels do not shoot good with rust and pits in the bore. Calibers with larger powder capacity seem to be more subject to rust and pitting damage. Barrels need to be cleaned from the chamber end and not the muzzle. Cleaning from the muzzle with out a muzzle guide will damage the bore and the muzzle.
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