.22 LR Muzzle Velocity drop

[chewbacca]

Okay, so I am looking for my first .22 LR pistol...

I am assuming that the muzzle velocity listed for most .22 LR ammo is for rifles.

Here are the questions I have...

What is the drop when fired from a short barrel?

and

How much more velocity would I lose using an automatic (I am looking at the Sig Mosquito and Ruger Mark III 5" Hunter) versus a revolver (I am looking at the S&W 617 6" 10 shot)?

Can anyone help me out? Thanks in advance.

 

[rnr]

I don't think you'll notice the difference. It's a .22. With the long barrels, you've burnt all the powder by the time it's past 16", so the rest is just momentum. So it looses a bit of velocity. With a pistol you're still burning powder when it comes out the barrel, which is why you see flame.
But again, I don't think you'll see a difference.

And of the 3 that you're looking at:
I've heard/read not so good things on the Sig.
I personally don't like the MKIII's, (I'd look for a good used MKII) but they're pretty decent. And isn't the hunter a bull barrel? You'll get good accuracy.
I really like the 617 and have read good things.

 

[David E]

Typical velocity with a .22 long rifle 40 grain bullet from a pistol length barrel is about 1250 fps.

Also consider the Browning Buckmark. I have the "Camper" version and like it quite a bit.

.

 

[chewbacca]

Thanks gents, I believe the Hunter is the same as the bull, but with a fluted barrel.

I may take a look at the Browning.

Right now the autos are ahead of the 617 in my race, only due to price...like $350 vs $650.

RNR, any thoughts on the 22/45 Mark III - I love my Kimber and was thinking the government model grips might be a nice feel. On the other hand a narrower grip might be appreciated by the wife!

 

[vwb563]

Okay, so I am looking for my first .22 LR pistol...

I am assuming that the muzzle velocity listed for most .22 LR ammo is for rifles.

Here are the questions I have...

What is the drop when fired from a short barrel?

and

How much more velocity would I lose using an automatic (I am looking at the Sig Mosquito and Ruger Mark III 5" Hunter) versus a revolver (I am looking at the S&W 617 6" 10 shot)?

Can anyone help me out? Thanks in advance.

typical velocity from high velocity 22lr are about 1100 to 1150 fps from most 4" barrel handguns. hyper velocity like cci stingers shoud get you about 1300 to 1350 fps. as far as more drop from an auto, the opposite is true. a 4" barrel semi-auto will normally get more velocity than a 4" revolver. (semi-auto's have no cylinder to barrel gap like a revolver. this is where revolvers loose velocity) i hope this helps.,,,VWB.

 

[hlee]

Semiautos lose velocity because they use some of the energy of the round to work the action. Semi-auto high powered rifles (browning BAR for example) can lose as much as 30% due to the need to work the action. Gas operated or blowback, you don't get something for nothing.

 

[David E]

RNR, any thoughts on the 22/45 Mark III - I love my Kimber and was thinking the government model grips might be a nice feel. On the other hand a narrower grip might be appreciated by the wife!

Another good choice. Since you already have a Kimber, either this one or the aforementioned Buckmark will work well for you as an understudy gun.

Another possibility: get a .22 conversion kit for your Kimber. You'll have the exact same trigger pull, controls, etc.

.

 

[Cougar Allen]

Semiautos lose velocity because they use some of the energy of the round to work the action. Semi-auto high powered rifles (browning BAR for example) can lose as much as 30% due to the need to work the action. Gas operated or blowback, you don't get something for nothing.

I can't imagine where you got that 30% figure. The actual velocity loss is insignificant, typically less than the shot-to-shot variation between cartridges from the same box.

 

[vwb563]

Semiautos lose velocity because they use some of the energy of the round to work the action. Semi-auto high powered rifles (browning BAR for example) can lose as much as 30% due to the need to work the action. Gas operated or blowback, you don't get something for nothing.

You are correct in gas operated semi-autos as in high power rifles. but not 30%. more like 10% or less. anyway, most .22lr semi-auto pistols are NOT gas operated. they use the blow back system which keeps the casing in the chamber until the bullet has left the barrel which leads to higher velocities than revolvers achieve. Im a firearms instructor and court testimony expert. so i know what im talking about. but thanks anyway for your input.,,,VWB.

 

[chewbacca]

Another good choice. Since you already have a Kimber, either this one or the aforementioned Buckmark will work well for you as an understudy gun.

Another possibility: get a .22 conversion kit for your Kimber. You'll have the exact same trigger pull, controls, etc.

.

I looked at the conversion kit for the Kimber, but for the same $$$ I figured I could have another pistol! My addiction is no longer limited to knives!

 

[David E]

I looked at the conversion kit for the Kimber, but for the same $$$ I figured I could have another pistol! My addiction is no longer limited to knives!

True, but the trigger pull will be different, as would the controls. The same holster and mag pouches can be used, as well.

But while there are good points to the conversion kit, there are good points to having a complete gun, thereby giving you two, not 1 and 1/2.

In that vein, go with the one that more closely mimics the grip angle of your Kimber, which would be the Ruger 22/45 and Browning Buckmark.

.

 

[hlee]

How much velocity is lost due to incomplete powder burn prior to the bullet leaving the the muzzle? In other words, what is the velocity difference between a 4" semiauto pistol and a 20" bolt action rifle? The energy to work the action has to come from somewhere. The only energy input is the explosive evolution of gas from the burning powder. This energy can be used to propel the bullet OR work the action- in a semiauto some propels the bullet, some works the action. Again, you don't get something for nothing. A high school physics student (you don't have to be a court testimony expert) could tell you that, but thanks anyway for your input. By the way, I've been shooting for a while, myself. One of the animals in my avitar is me, guess which one.

 

[rnr]

Thanks gents......
RNR, any thoughts on the 22/45 Mark III - ....

They're nice and you can get them w/ a bull or fluted barrel. I don't like the grip angle, tho.

I'm just kind of old school. I still like the MKII's.

I think the Buckmark would be a good choice too.

I can't imagine where you got that 30% figure. The actual velocity loss is insignificant, typically less than the shot-to-shot variation between cartridges from the same box.

Yup, you don't loose that much, very small.

 

[David E]

How much velocity is lost due to incomplete powder burn prior to the bullet leaving the the muzzle? In other words, what is the velocity difference between a 4" semiauto pistol and a 20" bolt action rifle?

Not as much as you are thinking. There have been several articles over the years where the writer took a .22 rifle and had the barrel cut, an inch at a time, measuring the velocity at each length. I cannot find it online, so we'll have to go with my recollection of the article. .22 Longrifle ammo reaches it's peak velocity around the 14-16" mark. This means that a .22 rimfire 16" bolt action will shoot the same round faster than a 20" bolt action. This is due to the powder being fully consumed before the bullet exits the barrel and coasts along, being slowed by friction the remainder of the distance.

The energy to work the action has to come from somewhere.

Yes, but not much is needed at all. The bullet is long gone by the time the action opens.

If you want maximum velocity out of each and every cartridge fired, then use a bolt or single shot gun. But even then, there are other factors at work. For example, my 16" semi-auto could easily have a higher velocity than your 16" bolt action. Why? Because in this example, my chamber is tighter than yours and maybe my barrel is sized better and is smoother.

The same applies to revolvers. A 6" should have a higher velocity than a 4" of the same caliber, but that's not always true. Variances in flash gap, chambers, chamber throats, forcing cone and barrel can easily tip the scales toward the 4" gun.

The bottom line, for me, is that if a .22 goes 1500 fps from a single shot bolt action and "only" goes 1490 fps from my semi-auto, I'll gladly take that hit for what the semi-auto gives me in return. Hell, standard shot to shot deviation accounts for more difference than that.

.

 

[spyder10]

Why does it matter if you lose a few hundred fps? What are you going to use it for? If it is target shooting then the velocity loss doesn't matter, especially considering how a .22lr drops.

If you plan on using it for hunting or pest control then the story might be different, but then a rifle would be a better choice anyway.

The whole issue kind of seems like a moot point to me...

 

[vwb563]

How much velocity is lost due to incomplete powder burn prior to the bullet leaving the the muzzle? In other words, what is the velocity difference between a 4" semiauto pistol and a 20" bolt action rifle? The energy to work the action has to come from somewhere. The only energy input is the explosive evolution of gas from the burning powder. This energy can be used to propel the bullet OR work the action- in a semiauto some propels the bullet, some works the action. Again, you don't get something for nothing. A high school physics student (you don't have to be a court testimony expert) could tell you that, but thanks anyway for your input. By the way, I've been shooting for a while, myself. One of the animals in my avitar is me, guess which one.

Partly true. But revolvers loose a lot of velocity because of the barrel / cylinder gap. And a high school student can also tell YOU that a COMPLETE open gap between the cylinder and barrel is gonna let pressure escape severly!

Blow back operated semi-auto's act as a bolt action in the scense that the breech stays locked until the bullet has left the barrel so nothing is lost ( gas pressure) until the bullet has already left the barrel as in the gas operated semi-auto's where gas is bled from the closed system to propel the bolt back. But as I said before, thanks for the input anyway. Buy yourself a chronograph and check some guns against one another and you will see what I'm saying is exactly correct. ,,,VWB.

 

[hlee]

vwb563, what you are saying is correct. I will give that. However, compared to the full potential of the round (as observed with a barrel that allows full expansion of the gasses prior to exit of the round, and an action that does not use the energy of the burning powder to chamber the next round), a semi-auto will give you less velocity. Because the burning powder has to "blowback" the action once the bullet has left the muzzle, it has to have sufficient energy to do that. It has to save some energy to push the action back. How does it do that? In part, firearm is designed with a barrel that is sufficiently short that the bullet can exit the barrel before all of the powder is burned. In this way, the powder is still burning when the action is "unlocked", and the remaining energy from the burning powder can be used to push the action back. The powder that is not burned while the bullet is in the barrel is potential lost.

David E brings up good points about gasses escaping through otherr means (around the jacket or around the bullet due to design tolerances), but all things being equal velocity of BA > velocity of SA.

Now I look at this from the perspective of the hunter, where velocity does matter, in lessening the effects of distance estimation and maximizing the downfield effects of the projectile.

The 30% value mentioned above is from one of those nebulus articles read, but not sufficiently remembered to find a concrete reference, but I believe it is from an article in an issuel of the North American Hunting Association Magazine. And, it is specifically in reference to high power hunting cartridges like the .30-06. The writer could have been in error, or strongly biased against semi-auto hunting arms, but I have no to support or refute either.

I hunt with bolt actiton rifles and o/u shotguns in part to eek out every last fps from every cartridge.

 

[David E]

The point is extremely, utterly moot.

"all else being equal" is rarely the case. I could show you semi-autos that have higher velocity than a bolt action. If a bolt action has powder burning out the end of the muzzle, then it didn't use all the available power/powder, so the velocity won't be as high.

Once the bullet is out of the barrel, it doesn't matter that the action is then cycled, as bullet velocity will not be increased/decreased one inch per second. It doesn't matter if there is powder burning outside the barrel, or if there isn't. The bullet velocity has already been achieved when the bullet leaves the barrel.

Evenso, the difference is SO MINOR that neither you, nor the target, will be able to detect the slight velocity difference, if any, is present.

.

 

[hlee]

I'm going to try this one more time.

Given the same cartridge(caliber, bullet weight and design, powder weight, primer, etc) a firearm that burns all of the powder in the same time (burn time) as the time it takes the projectile to transit from the chamber to the muzzle (transit time) will generate a higher velocity that a firearm with a transit time that is shorter than the burn time. By design, the transit time for a semiauto is shorter than the burn time. Therfore, a semiauto does not and can not use the full potential of the round.

I can detect the difference. the recoil of a semiauto shotgun is substantially less than that of a o/u in the same guage with the same loads. This differnece is due to the energy being syphoned off to work the action. This is true with both Beretta (gas operated) and Benelli (inertia driven) shotguns.

 

[enkidu]

How much velocity is lost due to incomplete powder burn prior to the bullet leaving the the muzzle? In other words, what is the velocity difference between a 4" semiauto pistol and a 20" bolt action rifle? The energy to work the action has to come from somewhere. The only energy input is the explosive evolution of gas from the burning powder. This energy can be used to propel the bullet OR work the action- in a semiauto some propels the bullet, some works the action. Again, you don't get something for nothing. A high school physics student (you don't have to be a court testimony expert) could tell you that, but thanks anyway for your input. By the way, I've been shooting for a while, myself.

Well, since high school physics has been mentioned and since I like to kid myself that I remember a lot of mine, I'll chime in.

First of all, you are confusing conservation of momentum and conservation of energy. Disregarding any quantum effects: momentum in a closed system stays constant. Similarly (but via totally different means/theories) total energy (chemical, gravitational potential, heat et al) in a system stays constant.

When the primer and powder in a cartridge is ignited, chemical energy is released in the form of heat and pressure. That increases the pressure in the cartridge which acts upon the base of the bullet as a force, causing the bullet to move forward, through the barrel and out the muzzle. Similarly, the pressure in the chamber pushes on the back of the cartridge which in a bolt action firearm is solidly attached to the frame and in the case of a blowback operated firearm, is attached to (or pushes against if you prefer) the mass of the bolt or slide. In the case of the Buckmark, the two are the same, in the case of the Ruger Mark II series, there is no slide, just a bolt which extends through the back of the frame. In either case, the mass is much much larger than the mass of the bullet and only a tiny fraction of the energy is converted into kinetic energy of the rearward moving mass.

Aside from the bullet, the vast majority of the rest of the energy is used in heating/pressurizing/accelerating the gases which result from the combustion. This comes in the form of the loud report of the gun fire and the blast of air from the muzzle. The muzzle blast gases move at a much higher velocity than the bullet (and since energy = 1/2 mv^2) carry a lot of energy despite the low mass of the gases. Incidentally, this is also why a contact wound from a firearm is many times more devastating than just the bullet from even a short distance. These gases can be redirected after the bullet exits the barrel to reduce the recoil experienced by the shooter by a muzzle brake. Note, any porting *before* the crown of the muzzle *will* reduce muzzle velocity slightly, but porting *after* the crown has practically no effect on muzzle velocity.

The *only* reduction in the kinetic energy of the bullet occurs by changing/reducing the force upon the bullet, force which is exerted by the pressure of the combustion gases on the base of the bullet. Yes, in a blowback operated 22lr firearm, pressure will drop very slightly because the size of the cylinder increases slightly due to the rearward movement of the bolt/slide, but given the extremely short amount of time it takes for the bullet to leave the muzzle, this reduction is negligible and many orders of magnitude less than 30%. A simple test for this theory would be to take a 22lr blowback pistol with a lockable slide or bolt and (with several identical batches of ammunition) fire rounds with the slide locked and the slide unlocked through a chronometer.

Given the above, a reduction in recoil does not necessarily mean that there is a corresponding reduction in muzzle velocity.

http://en.wikipedia.org/wiki/Physics_of_firearms is a good place for the bare basics of the physics of firearms. This page may also be useful: http://www.bsharp.org/physics/stuff/recoil.html .