I see this question asked a lot in groups and on forums I am a part of, and the best advice anyone can give you, including me, is that the perfect time to change the barrel is when it starts to impact your accuracy.
Now that you know the answer, let’s dive a bit further in and pinpoint when that might actually be, what causes barrel deterioration, and how to prolong the lifespan of the barrel.
How to Know When The Barrel Needs To Be Replaced
Like I said above, the definitive and only true answer is: The barrel should be replaced once the wear starts messing with your accuracy on your desired range.
There are so many variables that influence the lifespan of the barrel, for example:
- Barrel material
- Manufacturing process
- Ammo used
- Cleaning process and regularity
- Gas operated vs. recoil-operated
- And more…
See how many variables there are? However, there are some methods for detecting signs of barrel deterioration. Bore scope is one of them, but don’t go buying one if you don’t absolutely need or want to. Ask your friends or at the gun range, someone surely has it. Other options include a visit to the local gunsmith or a firearms store.
Word of warning: Barrels are pretty expensive, and you should check a few other things before making the decision to replace the barrel.
If you have a muzzle installed, check the muzzle crown. If damaged, it can greatly impact accuracy.
Some variables like an unstable stand, loose targets, and a windy day can also be the culprit.
Last but not least, if you have a scope, check if it’s mounted properly. Recoil also impacts your scope by loosening up the rings (Learn how to soften the recoil). One other thing you should check is if your scope holding zero because scopes sometimes lose it for a number of reasons.
How Many Rounds Before A Barell Starts Impacting Accuracy?
We will drop the whole variables argument here and determine an approximate lifespan of an average barrel, and we will set a requirement of at least 1 minute of angle accuracy.
The first thing you should know is that the barrels used for shooting slower rounds at lower pressure are going to outlast the barrels used for shooting magnums and varmints. This means that a barrel for a 22lr should last a very very long time, and take on several thousands of rounds before impacting accuracy.
The stock rifles used by the military are expected to last 10,000 rounds. And if you absolutely must have a definitive number, this could be it if you have a similar rifle.
However, the fluctuations between calibers and ammo types are just too great to list them all here. However, I would like to mention one example: I recently read an article where the author stated that his friend had a .220 Swift that didn’t even last 2000 rounds.
These few examples should enable you to pinpoint your barrels’ life expectancy a bit better but always take into account the human factor too.
Why Does Barrel Deterioration Happen?
More often than not, the throat of the barrel is the first to show signs of wear and tear. The throat is the part between the action and the rifling, it’s also the part where all the pressure and heat are.
The two main culprits that cause barrel deterioration are pressure and temperature. This means that by shooting the faster and stronger cartridges you cause the barrel to wear down faster. Even if you only use regular ammo, shooting long strings of bullets and not giving the barrel a chance to cool down will also have the same effect.
Another important factor is the cleaning technique you use for your barrel. I have seen some pretty energetic people cleaning their rifle like it’s a chimney, and with that technique, they would actually prolong the barrel life by not cleaning it at all.
Decreasing The Barrel Deterioration
By now you probably have a pretty good idea how to prolong a barrel’s lifespan so I am going to mention a few simple examples you can do without going into too much detail.
The first one is obvious – don’t use powerful cartridges if you don’t have to. I know they are fun but using cartridges with more punch than you actually need for the task is going to shorten your barrel’s life quicker.
The second is straight-forward – Let your barrel cool down by not shooting your entire mag at once. Even longer non-stop fire will heat up the barrel quickly which means a lot more stress. However, if you are required to shoot for longer strings, a bull barrel might be a good option. Just remember that the bulkier bull barrel also takes proportionally more time to cool down.
Third – Consider using a bore guide. Even if you are cleaning your rifle with care, a bore guide can reduce the damage of the rifling over time and in turn extend the lifespan of the barrel. This does not mean that you should stop cleaning your rifle, in fact, by not cleaning your rifle you will speed up the deterioration. I have read some works where the damage to the rifling caused during cleaning is portrayed as a massacre scene, which is totally false, but it can still happen.
I would like to point out that you don’t really need to worry about barrel wear because the truth is you will probably notice it if it starts happening. Also, note that hunters will probably never see their barrel’s deterioration to the critical point unless doing something that would mess it up.
Hobbyists and regular shooters, however, will probably change a few barrels simply because of the amount of ammo used.
By taking precautions based on what you now know, you will prolong your barrel’s lifespan and maintain accuracy longer.
If you have any questions or suggestions, please write them down in the comments section and I will make sure to address each one.
Also, if you would like me to write about something specific you are interested in, I would gladly publish a piece as soon as possible.