optimum Barrel length for 22lrs

Jdiep

Jdiep

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Hey I was reading that a 16.5" barrel length on a 22lr bolt action rifle is more accurate then a 21" barrel, is there any truth to that?

looking at the 2 savage mark II heavy barrel, one has a 21" and the other is 16.5" deciding which is better for accuracy.

Thanks.
 
Short and fat is where it's at. A shorter, wider object is much more sturdy than a longer/skinnier object. So yes, a 16" should have more inherent accuracy, and repeatability, than a similarly profiled longer barrel.
 
Jdiep said:
Hey I was reading that a 16.5" barrel length on a 22lr bolt action rifle is more accurate then a 21" barrel, is there any truth to that?

looking at the 2 savage mark II heavy barrel, one has a 21" and the other is 16.5" deciding which is better for accuracy.

Thanks.
Click to expand...

Allegedly the Mark II FVSR (16.5") is the one to have but it only comes in right hand so I probably won't be buying one anytime soon :)
 
After about 16 inches the bullet is traveling at max speed from the expanded gas, more barrel length can reduce the velocity but that doesn't mean it's less accurate.
 
Jdiep said:
Hey I was reading that a 16.5" barrel length on a 22lr bolt action rifle is more accurate then a 21" barrel, is there any truth to that?
Click to expand...
If it was true, you would see a lot of 16 inchers in benchrest competitions in US.
But in reality, you find exactly zero rifles with that barrel length.
 
I bought a used benchrest from the US. The gunsmith was Gorham, a very respected smith. It has two barrels which are 25.5".
 
An old fashioned advantage of longer barrels was when shooting with open sights: a longer sight radius means more potential accuracy with irons. Today most shooters looking for accuracy often use scopes. BR rigs use longer rather than shorter barrels. The length of the barrel itself does not necessarily make the rifle more accurate. What it can do is help cause the ammo to have a more consistent MV; this allows for more consistent trajectories with commensurate results for accuracy.

For most mortals shooting sporter .22LR rifles, a 16" barrel would hardly make a perceptible difference in the same rifle over a 22" or 24" barrel. Quite often the same holds true for varmint or heavy barrel vs. a thinner or sporter barrel. The bottom line is that for most of us shooting low-to-mid-range ammo (SK Standard Plus, for example), differences in accuracy accrue more from individual rifles than from one model to another, heavy barrel or sporter barrel. In other words, a good example of a sporter barrel of a given model will be very competitive with a good example of a given model with a varmint barrel. Neither the skills of the average shooter nor the ammo he uses allows for there to be considerable differences between barrel lengths or thickness.
 
grauhanen said:
An old fashioned advantage of longer barrels was when shooting with open sights: a longer sight radius means more potential accuracy with irons. Today most shooters looking for accuracy often use scopes. BR rigs use longer rather than shorter barrels. The length of the barrel itself does not necessarily make the rifle more accurate. What it can do is help cause the ammo to have a more consistent MV; this allows for more consistent trajectories with commensurate results for accuracy.

For most mortals shooting sporter .22LR rifles, a 16" barrel would hardly make a perceptible difference in the same rifle over a 22" or 24" barrel. Quite often the same holds true for varmint or heavy barrel vs. a thinner or sporter barrel. The bottom line is that for most of us shooting low-to-mid-range ammo (SK Standard Plus, for example), differences in accuracy accrue more from individual rifles than from one model to another, heavy barrel or sporter barrel. In other words, a good example of a sporter barrel of a given model will be very competitive with a good example of a given model with a varmint barrel. Neither the skills of the average shooter nor the ammo he uses allows for there to be considerable differences between barrel lengths or thickness.
Click to expand...

That is some real talk right here! thanks. That is good information.
 
grauhanen gave a very clear case for most of our 22 shooting with factory rifles. You need to tune each rifle with ammo selection.

I did a lot of ammo testing (aggregates), from the bench, with my Anschutz 54.18ms-ed. Barrel length 19.25", with a 14.25" barrel extension tube and 3 muzzle balance weights. I used premium ammo. Got hooked on rimfire accuracy. Decided time to upgrade.

I researched benchrest & learned a bunch. They select blanks & test each blank to determine it's ideal performance potential then run other tests to determine is ideal finished length. The guy I bought mine from uses two or more new rifles per year. He had over 20 blanks!

As part of my research before I decided to build or buy I bought 'The Art of Rimfire Accuracy' by Bill Calfee. The man is very controversial but he knows his stuff. The book is dated 2011 but still relevant. Has his own web site, again very controversial, that you can challenge or ask for updates.
 
grauhanen said:
An old fashioned advantage of longer barrels was when shooting with open sights: a longer sight radius means more potential accuracy with irons. Today most shooters looking for accuracy often use scopes. BR rigs use longer rather than shorter barrels. The length of the barrel itself does not necessarily make the rifle more accurate. What it can do is help cause the ammo to have a more consistent MV; this allows for more consistent trajectories with commensurate results for accuracy.

For most mortals shooting sporter .22LR rifles, a 16" barrel would hardly make a perceptible difference in the same rifle over a 22" or 24" barrel. Quite often the same holds true for varmint or heavy barrel vs. a thinner or sporter barrel. The bottom line is that for most of us shooting low-to-mid-range ammo (SK Standard Plus, for example), differences in accuracy accrue more from individual rifles than from one model to another, heavy barrel or sporter barrel. In other words, a good example of a sporter barrel of a given model will be very competitive with a good example of a given model with a varmint barrel. Neither the skills of the average shooter nor the ammo he uses allows for there to be considerable differences between barrel lengths or thickness.
Click to expand...

Can you explain how this occurs or reference a source that gives evidence ? - thanks
 
The relevant issue is always more consistent velocity rather than achieving a higher velocity. That said, the longer barrels allow for more complete burning of the powder.

The following is a good explanation:

"1) When talking about anything other than primer only CB caps (with muzzle velocities well under 500 fps) a longer barrel is not going to slow a .22LR bullet down. For standard velocity (including subsonic ammunition branded/marketed ammunition), high velocity and hyper velocity.22LR ammunition, the length of barrel required before a bullet starts to decelerate would be measured in yards, not inches. When the barrel length gets to 2 or 3 yards then you can start worrying about a loss of velocity.

2) With standard velocity and high velocity ammunition the sweet spot in barrel length for velocity loss or increase per inch is about 16 inches. Below this point you see noticeable losses in velocity for each in of reduced barrel length, while above this length the increase in velocity with each inch of additional barrel length is progressively smaller. But let me repeat this, adding more inches will not result in a lower velocity out to the practical 30-32" limits of .22LR barrels.

3) The variation in velocity tends to be lower in longer barrels as it provides for more consistent and more complete burning of the charge. Most target rifles have 28" to 30" barrels and that's not just for increased sight radius, but also for greater consistency in velocity.

What this means is that a given brand of .22LR SV or HV ammo that has an average velocity of 1190 fps (with an SD of perhaps 20 fps) in a 16" barrel , may only have an average velocity of 1225 fps (with an SD of perhaps 20 fps) in a 20" barrel and 1240 fps (with perhaps an SD of 10 fps) in a 28" barrel. So the average velocity will still be increasing slightly with increased barrel length, and the standard deviation in velocity will be getting smaller.


So the no bull#### answer is that optimum barrel length for .22LR is about 16". But that's optimum in terms of increases and losses per inch, not "maximum" velocity and "complete" powder burn.

Consider the AR-15. 18" is about optimum for gains in velocity per inch. Above that the increases per inch start to decrease, but we all accept the data that 20" velocities are higher than 18" velocities and that 24' velocities are higher than 24" velocities. In the other direction we all accept the data that 16" velocities are lower than 18" velocities and that velocity loss really starts to accelerate as the barrel lengths go from 16" to 14.5", 11.5" and 10". The same general concept holds in .22LR data.

Complete powder burning is also largely irrelevant, as its the pressure of the gas that matters. Even once the powder is burned the pressure is contained in the barrel and that pressure remains and the bullet continues to accelerate until the volume of the bore is great enough to accommodate the expansion of the gas needed to lower the force behind the bullet to the force retarding the bullet (due to aerodynamic drag and friction in the bore). That would require several yards in a HV .22LR round. If you doubt that then consider the distance needed for the propellant to "burn" in an air rifle. Pressure drives the bullet not heat or flames.

----

I should add all this is based on actual chronograph numbers with several types of .22LR SV and HV ammo, in barrel lengths of 5", 16", 22", 24" and 28". "

See the post by DakotaFAL https://www.ar15.com/archive/topic.html?b=6&f=11&t=404316

See also http://www.rimfirecentral.com/forums/showpost.php?p=5540289&postcount=38
 
grauhanen said:
The relevant issue is always more consistent velocity rather than achieving a higher velocity. That said, the longer barrels allow for more complete burning of the powder.

The following is a good explanation:

"1) When talking about anything other than primer only CB caps (with muzzle velocities well under 500 fps) a longer barrel is not going to slow a .22LR bullet down. For standard velocity (including subsonic ammunition branded/marketed ammunition), high velocity and hyper velocity.22LR ammunition, the length of barrel required before a bullet starts to decelerate would be measured in yards, not inches. When the barrel length gets to 2 or 3 yards then you can start worrying about a loss of velocity.

2) With standard velocity and high velocity ammunition the sweet spot in barrel length for velocity loss or increase per inch is about 16 inches. Below this point you see noticeable losses in velocity for each in of reduced barrel length, while above this length the increase in velocity with each inch of additional barrel length is progressively smaller. But let me repeat this, adding more inches will not result in a lower velocity out to the practical 30-32" limits of .22LR barrels.

3) The variation in velocity tends to be lower in longer barrels as it provides for more consistent and more complete burning of the charge. Most target rifles have 28" to 30" barrels and that's not just for increased sight radius, but also for greater consistency in velocity.

What this means is that a given brand of .22LR SV or HV ammo that has an average velocity of 1190 fps (with an SD of perhaps 20 fps) in a 16" barrel , may only have an average velocity of 1225 fps (with an SD of perhaps 20 fps) in a 20" barrel and 1240 fps (with perhaps an SD of 10 fps) in a 28" barrel. So the average velocity will still be increasing slightly with increased barrel length, and the standard deviation in velocity will be getting smaller.


So the no bull#### answer is that optimum barrel length for .22LR is about 16". But that's optimum in terms of increases and losses per inch, not "maximum" velocity and "complete" powder burn.

Consider the AR-15. 18" is about optimum for gains in velocity per inch. Above that the increases per inch start to decrease, but we all accept the data that 20" velocities are higher than 18" velocities and that 24' velocities are higher than 24" velocities. In the other direction we all accept the data that 16" velocities are lower than 18" velocities and that velocity loss really starts to accelerate as the barrel lengths go from 16" to 14.5", 11.5" and 10". The same general concept holds in .22LR data.

Complete powder burning is also largely irrelevant, as its the pressure of the gas that matters. Even once the powder is burned the pressure is contained in the barrel and that pressure remains and the bullet continues to accelerate until the volume of the bore is great enough to accommodate the expansion of the gas needed to lower the force behind the bullet to the force retarding the bullet (due to aerodynamic drag and friction in the bore). That would require several yards in a HV .22LR round. If you doubt that then consider the distance needed for the propellant to "burn" in an air rifle. Pressure drives the bullet not heat or flames.

----

I should add all this is based on actual chronograph numbers with several types of .22LR SV and HV ammo, in barrel lengths of 5", 16", 22", 24" and 28". "

See the post by DakotaFAL https://www.ar15.com/archive/topic.html?b=6&f=11&t=404316

See also http://www.rimfirecentral.com/forums/showpost.php?p=5540289&postcount=38
Click to expand...

I've seen photos of guys going overboard with their AR's, but a 24 foot barrel is taking it to a whole new level... Guess if they can't hit the target with the bullet they can always knock it down with the barrel.... Cleaning must be a ##### as well.
 
Dr.Lector said:
If it was true, you would see a lot of 16 inchers in benchrest competitions in US.
But in reality, you find exactly zero rifles with that barrel length.
Click to expand...

If they were in urban combat and shooting under lets say 100m(for a .22), and actually had to walk the gun around, they would very likely choose a short barrel. And they get to sit that 20 pound gun down on a bench. You aint packing that around the bush/gopher field. I use my 12.5 dlask bull on my 10/22 as a gopher gun that I carry around. I really couldn't tell a difference from the factory one accuracy wise. Some people say they are better. Just need a happy medium on weight. Dont see many or 28" heavy bbl custom benchrest .22s....but i havent really looked.

Id have to say short and fat too. But having the short bbl is real handy, for my applications anyway. If you want to sit and shoot groups on a bench, then maybe it wont matter to you. But if you like to boot around on a quad with something that fits in a backpack, and still smash gophers then I'd be leaning towards the 16" or shorter. Prob not gonna notice a hell of a difference unless you really stretch it out and use fancy ammo anyway.

Duff
 
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