The Gun Digest Book of .22 Rimfire. James E. House
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Moving a cartridge from the magazine into the chamber. Pulling the slide fully to the chamber requires the slide to be drawn back and released.
A great many semiautomatic handguns intended for plinking have sights that are not fully adjustable. It may be possible to move the rear sight laterally in its retaining notch, but there may be no provision for elevation adjustment. This may not be as bad as it sounds at first. Rimfire handguns for plinking are intended for use at short range. The targets may be no more than 10 to 15 yards, and at such distances small sighting errors are likely to be unnoticed. Moreover, the difference in point of impact caused by using different types of ammunition will be small enough that the average shooter will probably not notice the difference. Handguns having fixed sights are entirely practical for a lot of reasons. First, if the handgun is going to be carried in a holster, there is no possibility of changing sight settings by inserting or removing the gun from the holster. Second, fixed sights are sturdy enough that some bumps and scrapes can be endured without affecting the sight adjustment. That may not be the case with target pistols having precise, adjustable sights that are less robust. Third, at the average distance at which the handgun is used there may be no need to adjust the sights. Fourth, if you do not need adjustable sights on your pistol for its intended uses, there is no need to pay for them. High quality adjustable sights often add $20 to $50 to the cost. Firing at a 4-inch black circle at 50 yards is an entirely different matter as is trying to take squirrels at ranges of 25 to 30 yards. In these cases, the handgunner is looking for all the accuracy possible and that means adjustable sights that are set for the type of ammunition being used at the appropriate range. The same fine handgun with adjustable sights makes an appropriate piece of equipment for target shooting as well as an effective tool for hunting small game and pests.
In summary, if you plan to shoot pine cones and pop cans at short range, almost any rimfire handgun will serve well. A low-end model with a short barrel and fixed sights will work just fine. If you want a handgun that you can use to hunt small game and pests or if you want to participate in more serious target shooting, a model having a longer barrel and adjustable sights is in order. Whether the handgun is a revolver or autoloader will be dependent on your personal preference. There is a wider choice available in the case of semiautomatics and they are more popular than revolvers today. It is the opinion of many, including this author, that the revolver is generally safer for inexperienced users. With an autoloader, the pistol is ready to fire just as quickly as the action cycles and puts a fresh round in the chamber. With a revolver, immediately after a shot the hammer is down and the chamber in line with it holds an empty case. A double-action revolver can be fired again by pulling the trigger, but the long, heavy double-action pull is required which is not likely to be accomplished by slight pressure applied by an inattentive shooter. This is not so with the autoloader which requires only light finger pressure to fire again.
A few single-shot handguns are available. One often sees an article dealing with “handgun” hunting in which a single-shot pistol having a barrel as long as 14 to 16 inches is used on a piece that is chambered for a cartridge that is normally used in centerfire rifles. These “handguns” may even have a bolt action or break action that is identical to that used on some models of rifles. The stock has been cut off and reshaped to give a pistol grip, but in reality these “pistols” are short rifles. They almost always have scope sights attached. Instead of “handgun” hunting, the sport is more appropriately called “hunting with a short rifle with the stock cut off” hunting. In order to effectively use a cartridge that is normally used in rifles, the barrels are of necessity longer than those used on handguns. In the area of rimfire handguns, there are a few single shot models and in calibers like 22 WMR and 17 HMR they are effective for hunting and pest control. As a handgun for the general uses for which rimfire handguns are appropriate, the single-shot is really a minor player in a big game.
Calibers
Along with the type of action, the choice of caliber needs to be made. In rimfire rifles, identical models are available in 22 LR, 22 WMR, and 17 HMR calibers and some are also available in 17 Mach 2. This is by no means the case with handguns, and comparable models are not always available. One outstanding exception is the Ruger Single Six convertible, which comes with one cylinder that chambers the 22 LR and another that chambers the 22 WMR. It is possible to offer a combination such as this even though the bullet diameter for the 22 LR is 0.223” while that for the 22 WMR is 0.224” and the small difference causes no problems. This is a single-action revolver that gives the shooter the choice between two power levels (and price levels in ammunition). Another manufacturer that offers a single-action revolver with two cylinders is Heritage. Some older Harrington and Richardson revolvers offer two cylinders and can be found on the secondary market.
One factor to consider when discussing handgun calibers is the difference in velocity that results from the short handgun barrel compared to that of a rifle. The 22 LR develops maximum velocity while traveling approximately 16 inches in a rifle barrel. If the barrel is longer than about 18 inches, the velocity actually decreases slightly because of being slowed by friction. In a 6-inch handgun barrel, the velocity produced by a given load is somewhat lower than it is when the same load is fired in a rifle. In most cases, there is approximately 125 to 150 ft/sec difference between the velocity produced by a 6-inch barreled handgun and the velocity given by the same load in a rifle. Moreover, because there is a gap between the cylinder and barrel in a revolver (usually 0.002 to 0.008 inches), some gas escapes through this gap and is not used to push on the bullet. As a result, a revolver having a given barrel length generally gives lower velocity than that produced by a semiautomatic having the same barrel length and firing the same type of ammunition. Incidentally, barrel length of a revolver does not include the cylinder in the measurement. The barrel length for a semiautomatic is the distance from the breech to the muzzle.
Rimfire handguns are produced in the (left to right) calibers 17 Mach 2, 22 LR, 17 HMR, and 22 WMR.
The fraction by which the velocity from a handgun is lower than that given by a rifle depends on several factors. First, even with the same barrel length (which does not include the length of the cylinder), a revolver will generally give a velocity that is approximately 50 ft/sec lower than that of a semiautomatic. As will be discussed in Chapter 7, most types of ammunition give about the same velocity from a 6-inch barreled revolver as from a semiautomatic having a 4.5-inch barrel. Of course, the length of the gap between the cylinder and barrel has a significant effect. A gap of 0.003 inches results in less velocity loss than does a gap of 0.007 inches.
A semiautomatic with a 5.5-inch barrel will give approximately 50 ft/sec higher than one with a 4.5-inch barrel (see the table of velocities presented in Chapter 7). It should be remembered that there are other factors that influence bullet velocity from semiautomatic handguns. Dimensions of the chamber and bore as well as bore smoothness have some effect on velocity. Therefore, it is possible for a particular handgun with a 4-inch barrel to give velocities that are as high or higher than those from another specimen with a 4.5 or 5-inch barrel.
As a result of their using larger charges of slower burning powders, some of the hyper velocity loads in 22 LR suffer a greater loss than do ordinary cartridges when fired in handguns. This effect is even greater in 22 WMR and 17 HMR calibers which need longer barrels to allow the powder charges to burn efficiently. In a handgun with a 6-inch barrel, the 40-grain 22 WMR bullet that is driven to about 1,900 ft/sec in a rifle achieves only approximately 1,450 to 1,500 ft/sec which generates an energy of almost 200 ft lbs. Although energy this high does not make a 22 WMR handgun a better choice than most centerfire calibers for defensive uses, it is more effective than a 22 LR, 25 Auto, and some other lowpowered calibers. While they cannot fire ammunition of any other caliber or accept another cylinder,