I'm getting ready to order a dedicated .22LR upper and I'm wondering if a 20" bbl is any better or worse than a 16" bbl. Obviously, sight radius is better when using irons but does a 20" bbl allow enough velocity (when compared to a 16") to make a difference? I'm only going to be using this for plinking so I'm not really concerned about any velocity difference between the 2 bbl lengths but if there's a benefit to the longer bbl (besides the irons sights), I'd like to know.

Thanks in advance.

ETA: BTW, My "plinking" would be up to 100 yds, heck maybe even 200 if I'm feeling daring.  The fact is I can't find any info on .22LR ballistics from 16" vs. 20 bbls.  

.22lr velocity is pretty much optimum at around 14-16" barrel.  Depending on the exact cartridge this will change slightly, and some cartridges will increase velocity very very slightly with longer barrels, but you are wasting your time.  Everything else being equal, accuracy is better in a shorter barrel, less wip, less barrel time from moment of discharge, less weight, etc...  The only advantage to a 20" is sight radius.  And you can match the rifle sight radius with a 16" barrel if you use a 12" free float rail with the front sight at the end of the rail.

i shoot 100 yards with my 5" .22LR upper, so 16 or 20 should be fine

Quoted: .22lr velocity is pretty much optimum at around 14-16" barrel.

That is precisely what I needed to know. Thank you.

Depending on the exact cartridge this will change slightly, and some cartridges will increase velocity very very slightly with longer barrels, but you are wasting your time.

Again, spot on. I just wanted to make sure that I wouldn't be missing some benefit velocity-wise from a longer bbl.

Everything else being equal, accuracy is better in a shorter barrel, less wip, less barrel time from moment of discharge, less weight, etc...

Check on all of that. I used to have an image that was data from a test that Thunder Ranch did with bbl length vs. accuracy. The shorter bbl was the winner.

The only advantage to a 20" is sight radius.  And you can match the rifle sight radius with a 16" barrel if you use a 12" free float rail with the front sight at the end of the rail.

Yes, I could do that but I'm looking to put an FF handguard on it at this time but if I do, I may go that route.

After thinking about this overnight, I'm going to get a 20" upper and have it chopped down to 16".

One more consideration for you: The 16" barrel will be louder.

I can shoot a 20" .22 without ear protection no problem at all. The 16" without ear protection is sometimes disturbing, I guess depending on temperature, pressure, humidity and so forth or whatever. So I sometimes use ear protection when shooting the 16". And I ALWAYS have to use it if my kid is shooting the 16" right next to me.

16" is a good compromise for accuracy. I have a 16" V22 and a friend has one cut down to 12.5". No difference in close, but beyond 40-50 yards his doesn't group as well. Mine is good for @2" groups at 100yards. Handling? well I can't tell the difference by losing 3.5". A shorter stock would make a bigger difference

Quoted: One more consideration for you: The 16" barrel will be louder. I can shoot a 20" .22 without ear protection no problem at all. The 16" without ear protection is sometimes disturbing, I guess depending on temperature, pressure, humidity and so forth or whatever. So I sometimes use ear protection when shooting the 16". And I ALWAYS have to use it if my kid is shooting the 16" right next to me.

That's a very good point. My friend has a bolt action Savage .22LR which is very quiet. Although I don't recall the bbl length on it, I know exactly what you mean. There is something to be said for having a quieter rifle.

Quoted: 16" is a good compromise for accuracy. I have a 16" V22 and a friend has one cut down to 12.5". No difference in close, but beyond 40-50 yards his doesn't group as well. Mine is good for @2" groups at 100yards. Handling? well I can't tell the difference by losing 3.5". A shorter stock would make a bigger difference

That's good info. Thank you.

For the time being, I'll be using the .22LR AR upper with one of my existing lowers and it does have a collapsible stock. When I do get around to getting a dedicated lower for it, it will have a collapsible stock.

Also, after I looked on Ruger's website at the 10/22s, the predominant bbl length for that series of rifles is 18.5". That makes me wonder about just having the bbl cut down to 18".

Bah, I just need to do some more digging on the Net to see if I can dig up some actual numbers to help me objectify this decision. Regardless, I'll buy a 20" upper and see how it goes.

Thanks for all the help folks.

I think the common 18.5" barrel length is due to Canadian law, not ballistics.

I'm not 100% on this but I believe a rifle has to have an 18.5" barrel to be unrestricted and therefore legal to hunt with in Canada. They can have 16" barrels, but then they are considered restricted and only for target shooting, if my info is correct.

Just like many other firearms laws, ballistics has nothing to do with it.

Quoted: Quoted: One more consideration for you: The 16" barrel will be louder. I can shoot a 20" .22 without ear protection no problem at all. The 16" without ear protection is sometimes disturbing, I guess depending on temperature, pressure, humidity and so forth or whatever. So I sometimes use ear protection when shooting the 16". And I ALWAYS have to use it if my kid is shooting the 16" right next to me. That's a very good point. My friend has a bolt action Savage .22LR which is very quiet. Although I don't recall the bbl length on it, I know exactly what you mean. There is something to be said for having a quieter rifle.

I have a Winchester 52B with a 28" barrel and it is way quieter than my 10/22 which has a 18" barrel.

Quoted: 16" is a good compromise for accuracy. I have a 16" V22 and a friend has one cut down to 12.5". No difference in close, but beyond 40-50 yards his doesn't group as well. Mine is good for @2" groups at 100yards. Handling? well I can't tell the difference by losing 3.5". A shorter stock would make a bigger difference

That is more telling of the crown than the barrel length.

Quoted: Quoted: Quoted:One more consideration for you: The 16" barrel will be louder. I can shoot a 20" .22 without ear protection no problem at all. The 16" without ear protection is sometimes disturbing, I guess depending on temperature, pressure, humidity and so forth or whatever. So I sometimes use ear protection when shooting the 16". And I ALWAYS have to use it if my kid is shooting the 16" right next to me. That's a very good point. My friend has a bolt action Savage .22LR which is very quiet. Although I don't recall the bbl length on it, I know exactly what you mean. There is something to be said for having a quieter rifle. I have a Winchester 52B with a 28" barrel and it is way quieter than my 10/22 which has a 18" barrel.

With 10" difference in bbl length, I sure t'heck hope you can hear a difference in volume between them.

Quoted: Quoted: 16" is a good compromise for accuracy. I have a 16" V22 and a friend has one cut down to 12.5". No difference in close, but beyond 40-50 yards his doesn't group as well. Mine is good for @2" groups at 100yards. Handling? well I can't tell the difference by losing 3.5". A shorter stock would make a bigger difference That is more telling of the crown than the barrel length.

That's a very good point. In general, shorter barrels are more accurate than longer ones. Even when we're dealing with the limited ballistics of .22LR, 3.5" of barrel and the lengths you're dealing with, the accuracy differential between the two rifles should not be that great.

In the course of doing research on .22LR rifles, I've consistently read that a good crown is essential if one wishes to obtain or maintain any type of decent accuracy.

Quoted: In general, shorter barrels are more accurate than longer ones. Even when we're dealing with the limited ballistics of .22LR, 3.5" of barrel and the lengths you're dealing with, the accuracy differential between the two rifles should not be that great. In the course of doing research on .22LR rifles, I've consistently read that a good crown is essential if one wishes to obtain or maintain any type of decent accuracy.

The discussion of barrel length and accuracy is tricky.  It has to do with the harmonics of the barrel as the round is fired and where the muzzle is in relation to the sine wave created on firing.  Given the same weight, I'd expect a shorter, fatter barrel to be more accurate - not because it's shorter, but because, for the same weight, it would be stiffer.  This is also why barrel tuners work - they manipulate the vibration pattern of the barrel.

And a good crown is critical to accuracy in any caliber.

A 22lr. barrel should be atleast 18in.  that's what it takes to burn all the powder.  

Quoted: A 22lr. barrel should be atleast 18in.  that's what it takes to burn all the powder.

Interesting. That contradicts the second post in this thread which stated 14"-16" was optimal for letting the round achieve maximum velocity.

What you're stating makes sense based upon the average barrel lengths for Ruger 10/22s (18.5").


I need to continue to scour the Net for more information on the subject. I just want to make sure I will be happy with my purchase.

Quoted: A 22lr. barrel should be atleast 18in.  that's what it takes to burn all the powder.

???????

It is my understanding that a .22 (generally) burns all of the powder you can squeeze into that tiny case in about 12" of barrel length.

The same ammo shot out of my S&W 622 chronographs at a higher velocity compared to being shot out of the long barrel (can't remember the length) on my Hainal bolt rifle.   My understanding is that the barrel is actually starting to slow down the bullet since the volume of the barrel has exceeded the volume of propellant gases available for acceleration.  

BTW - The Hainal is very quiet and will shoot sub 1" at 100 yards if the wind isn't blowing.

hell no. guns are like, the inverse, of your penis.

SMALL is GOOD.

seriously, it's a .22. are you really going to be worried about ballistics at 200 yds? unless you are shooting smallbore competetively, which if you were you wouldn't be here asking our opinion on the subject, there is really no need for anything longer then pistol length.

my second most accurate .22 i have right now is a ruger 10/22 SBR with an 11.5" barrel. at 40 yds, it'll pile them right up.

Quoted: hell no. guns are like, the inverse, of your penis. SMALL is GOOD. seriously, it's a .22. are you really going to be worried about ballistics at 200 yds? unless you are shooting smallbore competetively, which if you were you wouldn't be here asking our opinion on the subject, there is really no need for anything longer then pistol length. my second most accurate .22 i have right now is a ruger 10/22 SBR with an 11.5" barrel. at 40 yds, it'll pile them right up.

I agree with that to a point but obviously when   fragmentation is dependent upon velocity (e.g. 5.56), a longer barrel can be helpful.

The only reason I started this post was to find out how the length of the bbl affected the .22LR round.

Since I cannot get an SBR in my state and I don't want a extra long flash hider, I'll start with a 16" carbine bbl and possibly get it chopped to 14.5" (or 14.7" w/a permanently attached flash hider (A2 w/14.7" or Phantom with 14.5").

Thanks again for all the input folks.

Quoted: Quoted: A 22lr. barrel should be atleast 18in.  that's what it takes to burn all the powder.   ???????

Explanation below:

Many tests on how barrel length affects muzzle velocity have been done with the .22 Long Rifle, and from those experiments it has been concluded that generally any barrel length greater than 18 inches is actually causing the .22 LR bullet to slow down. The precise optimal barrel length for a .22 will vary from one load to another and one gun to the next because of different powder charges in the loads and tolerances in the bore dimensions. Regardless, the reason for the bullet slow down at that short a barrel length is because the expansion ratio (the sum of the volume of the bore and powder chamber divided by the volume of the powder chamber) for the .22 LR is so high. In other words, it has a very small powder chamber relative to the bore.

As powder burns it increases in volume about 1000 times, which increases pressure if contained as within a chamber. That pressure starts the bullet down the bore against the engraving forces, bullet-on-bore friction and the pressure of the air in the bore in front of the bullet. As the bullet travels down the bore, the volume of the space behind the bullet is increasing such that after reaching a certain point, gas pressure no longer increases.

After an inch of barrel was cut off, the muzzle was crowned and 20 shots were chronographed and averaged to determine what length was optimal for highest velocity.

Eventually, the gas pressure and bullet friction reach a point of equilibrium, followed by a transition to the effects of bore friction being greater than gas pressure. If the bullet is still in the bore after that transition, it slows down. While it happens at around 18 inches in a .22 LR, it would take a barrel several feet long in a cartridge such as the .308 Winchester because it has a much lower expansion ratio. The closer you get to optimal barrel length for maximum velocity, the less significant each increase in velocity becomes, which is why we get along fine with sporter barrel lengths in centerfire rifles.

I'm heavily leaning towards buying a complete .22LR M-4 from Spike's so I don't have to mess around with the whole deal. I'll just buy the rifle, some mags, a truckload of ammo and be done with it.

Besides, with a Spike's M-4, I can have my cake and eat it to in regards to bbl length. Spike's recesses the barrel 1.5" so you end up with the same amount of bbl past the FSB while retaining a 16" overall bbl length.