Published velocities for .22 Long Rifle cartridges are generally available for rifle length barrels. Finding the velocities for pistol length barrels is more difficult. Searches on the Internet did not yield results for several of the subsonic .22 Long Rifle cartridges. This article shows velocities measured from three pistols for five different cartridges.
Velocities in a particular barrel length can vary with individual barrels. Some barrels are smoother than others. Even the temperature of the cartridge, when the round is fired, can make a measurable difference. To see the differences for pistol length barrels, three handguns were used, because they were handy and were threaded for suppressors. The use of a suppressor can affect velocity, but the amount is usually small, and can be in either direction. Different lots of the same ammunition may have differences in velocity, usually small.
The three pistols used were a Kel-Tec CP33 with a 5.5 inch barrel, a Taurus TX22 with a 4.1 inch barrel, and a Kel-Tec P17 with a 3.93 inch barrel.
The cartridges tested were, in order of published velocities:
- CCI 45 grain Quiet .22 Semi-Auto 835 fps
- Aguila 60 grain SniperSubSonic 950 fps
- Federal American Eagle 45 grain suppressor 970 fps
- Winchester 45 grain Super Suppressed 1060 fps
- CCI Standard Velocity 1070 fps
Velocities shown in the chart are the average for five shots. The temperature varied form 56 to 76 degrees Fahrenheit. Velocities were measured 10 feet from the muzzle, with a Caldwell Chronograph G2. Five shots should be sufficient to give a good idea of pistol velocities from 4 and 5.5 inch barrels. Differences between the 4.1 inch and 3.93 inch barrels were expected to be small.
As can be seen from the chart, all of the rounds tested were reliably subsonic from the pistols tested. While the speed of sound varies with temperature, even at 40 degrees below zero, the speed of sound is above 1000 fps. As the temperature rises, so does the speed of sound. At freezing, it is 1087 fps. At 70 degrees Fahrenheit, it is 1128 fps. At 100 degrees F, it is 1159 fps. Atmospheric pressure has little effect on the speed of sound. As relative humidity increases, there is a slight increase in the speed of sound, just a few fps. It is expected few shots will be fired from a suppressed .22 pistol at temperatures lower than 40 below zero.
As a purely subjective measurement, the quietest ammunition, from a suppressor, was the CCI Quiet .22 Semi-Auto. The next quietest was the Federal suppressor American Eagle 45 grain load. The CCI Standard Velocity seemed a little louder. The Winchester 45 grain was a bit louder yet. The Aguila 60 grain SniperSubSonic seemed to be the loudest. It appeared to contribute considerable noise from the chamber area, perhaps because of the short case. With a suppressor, it was much quieter than fired without a suppressor. Subjectively, it seemed to be the noisiest. This writer suspects it would do best out of manually operated rifles.
The average difference in velocity between the 5.5" barrel and the 3.93" barrel, looking at all five cartridges, was only 25 fps. The 4.1 inch barrel was in between.
The 60 grain bullets of the Aguila need a faster twist than 1 in 16 inches to stabilize properly. The Kel-Tec CP33 and P17 both have 1 in 14 twists, which seem to stabilize the long bullet a little better. The new Taurus Compact TX22 has a 1 in 10 twist, which should stabilize the 60 grain Aguila load. It has a 3.6 inch barrel, so velocities of about 750 to 760 fps would be expected out of the shorter barrel, with the 60 grain bullet.
©2023 by Dean Weingarten: Permission to share is granted when this notice and link are included.
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The two shot at the top of the calipers to the left on the target. think of the shpt farthest to the left then the second shot to the right closest to the first hole then a third sot that closed the distance between those first two making the second hole slightly larger would be like the group I fired at a pistol competition and the judge of the competition claimed no body could be that good at 25 meters and refused to give me the prize money. Said I must have missed the target with the third shot.. I was sort of disappointed . My trigger pull was off, I had not had my hands on that pistol for six months or there would only have been one hole instead of two. It was only 25 meters and I am far sighted. I fired the first shot and aimed at that one and the space between the two holes was how much my trigger pull was off. That was the day Owen Ford offered me a job on the spot.
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