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Rusty Hook
02-27-2006, 09:03 AM
Barrel length vs velocity seems to always be a topic of interest to most hunters. But with the 22LR cartridge, rifle length barrels can actually reduce the velocity potential of this round.

In the VOL. 9, NO. 4 issue of GUNS & AMMO magazine, Bob Milek wrote an article titled: BARREL LENGTH VS VELOCITY, where he took a number of barrels and guns and cut down the barrels in one inch increments, measuring the velocity loss at each step of the process for a number of centerfires as well as the 22LRs. It's a very interesting article. Here are the velocities recorded for the 22LR starting at 14 inches and going down to 4 inches.

14" = 1,105 fps.
13" = 1,106
12" = 1,110
11" = 1,089
10" = 1,114
..9" = 1,077
..8" = 1,063
..7" = 1,057
..6" = 1,024
..5" = ..959
..4" = ..927 fps.

The 11 inch velocity was an anomoly which turns up from time to time in nearly all firearms testing. As can be seen, any barrel length between 6 and 10 inches will produce very acceptable velocities and energies with the 22LR. Different brands of ammo will produce some minor velocity variations, but not enough to make all that much of a difference in performance. The above tests were conducted with Winchester HV Solids.

In the 1986 issue of SHOOTING TIMES, in an article titled: T/C's SENSATIONAL NEW SHOOTING SYSTEM, the following velocities were recorded for 22LR high velocity loads.

10" = 1,229 fps ...4 group R-P 36-Gr HP REM HV
10" = 1,498 fps ...9 group CCI 32-Gr HP STINGERS
10" = 1,417 fps 1.1 group W-W 29-Gr HP EXTREEMES

In the same article the following comparison was made for different firearms, action types, and barrel lengths with 22LR ammo, given with R-P HV HP ammo:

Colt New Frontier..Sa Revolver.. 4 3/4" ..996 fps
S&W Mod 17 K-22....Da Revolver.. 6".... 1,092 fps
Ruger Single 6.....Sa Revolver.. 6 1/2" 1,028 fps
S&W Mod 41.......Auto Pistol.... 7 3/8" 1,087 fps
S&W Mod 17 K-22....Da Revolver.. 8 3/8" 1,049 fps
Sako Mod 78......Bolt Rifle.... 22 1/2" 1,219 fps
T/C Contender. S/Shot Pistol....10".... 1,229 fps
REM. Factory Data.... Test BL...18 1/2" 1,280 fps

An interesting point is that revolvers, irrespective of barrel length, showed much less velocity loss than is usually attributed to them compared to the closed breach auto or T/C Contender firearms.

As can be seen from the above tests, while individual barrel variations will happen due to the individual barrel or firearm being used, barrels longer than 10 inches yield very little additional velocity with the 22LR cartridge. A backpacking, live off the land, type hunter need not feel handicaped in using a revolver or a single shot pistol because of its shorter barrel length compared to carrying a 22 rifle for small game procurement...Rusty.

poel
02-27-2006, 09:57 AM
Rusty - Excellent post, thanks. I remember seeing that barrel length data years ago but had forgotten where the point of diminishing returns was.

It is interesting that .22 shorts from a 16" barrel are almost noiseless, perhaps because gas pressure has pretty much dissipated in the barrel. At what barrel length would a .22 slug cause the pressure to go to zero? If momentum carried it further, it seems you could eventually develop negative pressure. And if you had a moly coated bore and very low friction, could you eventually suck the slug backwards again?

Seems the 16" barrel is safe enough, so I'll stick with that for a rifle.

ThePrepared_com
02-27-2006, 10:02 AM
So the 10" Ruger MK II may be a great choice for a survival do it all .22lr. Gun laws are holding us back from producting a cost effective optimum barrel length .22lr rifle /images/%%GRAEMLIN_URL%%/smile.gif

Jim N
02-27-2006, 11:20 AM
The speed of sound at 50 F is 1107 fps. Keep the velocity under that (shorts, subsonics, etc) & the crack from the projectile breaking the sound barrier is eliminated.

I have seen remington subsonics bounce off the skull of a downed deer. Not the best option for putting a wounded animal down.

Rusty Hook
03-01-2006, 08:43 AM
The laws may be limiting what can be done with a rifle, but the field is wide open with respect to handguns if you don't mind giving up that stock.

Personally, I use a 14 inch S/S match chambered Contender barrel as an understudy for similar centerfires. I wanted the weight, ballance, action, trigger and scope to be as close as possible to what I deer hunt with.

But if I had been interested in getting a 22LR just for the sake of a 22LR, I would have gotten a similar barrel in a 10 inch length and had a lighter and handier gun to carry with slightly better velocities being produced out of the shorter barrel. Someday I may buy that shorter lighter barrel just for kicks, but I wouldn't want to give up the cheap and effective practice I get with the 22LR barrel I have, and investing in another scope wouldn't be cheap, so the shorter barrel doesn't seem very cost effective to me right now.

I see myself as being more of a user than a collecter of barrels and firearms. I don't get to use what I have enough now as it is, and I'm sure I have lots of company in that regard, Rusty.

poel
03-01-2006, 10:37 AM
Rusty - Here's a quick plot of Milek's data. The irregularities in the curve make you suspect some variance in the ammo, but the wow at 10-11" makes you wonder if that's where the gas quits expanding and the bullet goes into momentum mode, or if it's measurement related. Gotta wonder what causes that. If it is a persistent effect, you'd think it would occur in different places with different types of ammo. Could it be the influence of a sonic shock wave? In any case, it doesn't look like there is a significant penalty for the slightly longer barrel. In the other data, the Sako rifle does pretty well and the 18" test barrel gets em zinging. So where can we get Remington test barrels?


http://i23.photobucket.com/albums/b382/poel01/Vel22.jpg

elmbow
03-01-2006, 07:20 PM
I have short barreled 22 pistols, S&W 422, Colt Frontier Scout, Ruger Bearcat and hardly ever use them for the simple fact that when I'm out plinking I like to shoot without ear protection. They are all way too loud for that. I find the noise level of a 10" barrel pistol the minimum my ears will allow without protection. One of the nicest aspects of shooting 22 rifles is the quiet report. Velocity really isn't an issue for me in a 22 as I rarely shoot at targets over 50 yards. There are other calibers for yardages beyond that.

Rusty Hook
03-04-2006, 04:37 PM
Poel: I also wondered about the Rem Pressure barrel, I think it may be that it is super polished after all the tests which have been run through it from testing every lot of ammunition which they make. Another possibility is the factory data may have some public PR included to help sell their products.

In the first article, these tests were 10 shot crono'ed averages run by Milek, all with the same lot of factory winchester ammo. Even in the same lot of ammo, there will be variances. The center fire tests done also had some similar descrepencies. If you have ever done any work with a crono, you will realize, I'm sure, that unexplained anomolies are often just part of the process. You look mostly at the general and most consistent trends and directions and ignore the anomolies as long as they are anomolies, which usually requires more testing and ammo.

Elmbow: I was recently doing some plinking with a friend who was using a Colt Woodsman, with a 6 1/2 inch barrel I think. I was shooting my Contender with a 14 inch barrel. Mine was quieter but not as much as you might think it should be. My hearing is already so bad that I can shoot my 14" barrel with std. v. loads and it isn't uncomfortable to me at all with out ear protection. The same with a 20 Ga shot gun and 7/8 oz dove loads. I'm not saying that's normal or the way it should be; it's just the way it is for me at this point in my life.


I have another friend who has a super light weight 22 LR revolver. I don't remember the make or model, but the cylinder gap makes for a much noiser gun, so there may be a sizeable difference between wheel guns and closed breach pistols with respect to the noise levels they are producing regardless of barrel length. I don't think velocity is an issue either. I just wanted to point out that 22 LR pistols have much less velocity loss associated with them compared to rifles than centerfire firearms have. In a pistol, the 22 LR is about as good as it gets...Rusty.

elmbow
03-04-2006, 04:56 PM
Rusty, I agree 100% on the cylinder gap on wheel guns being a noise culprit. My Frontier Scout is a 6 1/2" bbl and it's tons noisier than my Ruger Mark II with its 10" Tactical Solutions bbl. The difference between the Woodsman and the Mark II or T/C wouldn't be as much TBS.