When choosing ammunition for a suppressed .22 LR firearm, it is natural to look for the quietest option available.
Less velocity generally means less noise. If the bullet remains below the speed of sound, it avoids the sharp ballistic crack produced by a supersonic projectile. Combine that with a suppressor, and the result can be remarkably mild.
But quietness is only one part of ammunition performance.
A load can be extremely quiet and still be the wrong choice for a particular firearm. It may not generate enough energy to operate a semiautomatic action. It may produce less velocity or energy than the shooter needs. It may also behave differently depending on whether it is fired through a rifle or a pistol.
Tom at Triumph Sporting Arms saw this firsthand while testing CCI Quiet alongside several other .22 LR loads.
CCI Quiet produced the lowest velocities and the mildest perceived report of the ammunition tested. It also failed to cycle the semiautomatic Ruger Mark IV used in the test.
That does not make it bad ammunition.
It means that quietness and practicality are not always the same thing.
Tom tested 15-round samples through two suppressed firearms:
CCI Quiet uses a 40-grain bullet and is designed to operate at substantially lower velocity than standard- or high-velocity .22 LR ammunition.
The chronograph results reflected that design:
| Firearm | Average Velocity | Standard Deviation | Extreme Spread | Energy |
|---|---|---|---|---|
| 18-inch rifle | 760 fps | 20.2 fps | 84 fps | 51 ft-lbs |
| 4.4-inch pistol | 652 fps | 9.8 fps | 37 fps | 38 ft-lbs |
CCI Quiet was the slowest load tested through both firearms.
For comparison, Federal Suppressor averaged 873 fps from the rifle and 879 fps from the pistol. CCI Standard Velocity averaged 1,103 fps from the rifle and 961 fps from the pistol.
The lower velocity contributed to CCI Quiet’s mild perceived report, but it also reduced the amount of energy available to operate the pistol’s action.
A semiautomatic firearm uses energy from the fired cartridge to operate its action.
In a blowback-operated .22 LR pistol such as the Ruger Mark IV, the pressure created by the cartridge pushes the cartridge case and bolt rearward. That movement extracts and ejects the fired case, resets the action, and loads the next round.
If the ammunition does not generate enough energy to move the action through its complete cycle, the firearm may not function automatically.
Possible results include:
During Tom’s test, CCI Quiet did not cycle the Ruger Mark IV.
The ammunition fired, but the pistol could not complete the normal semiautomatic operating cycle.
That result should not be interpreted as a defect in either the firearm or the ammunition. The load simply did not produce enough energy to operate that particular firearm and suppressor combination reliably.
The cycling limitation becomes much less important in a manually operated firearm.
A bolt-action rifle does not depend on cartridge energy to load the next round. The shooter manually lifts and operates the bolt after each shot.
That makes a bolt-action rifle a natural platform for very low-velocity ammunition.
In that setting, CCI Quiet may offer several useful qualities:
The Ruger Precision Rimfire used in Tom’s testing is manually operated, so the shooter does not expect the ammunition to cycle the firearm automatically.
This allows the shooter to take advantage of the lower sound level without sacrificing the firearm’s basic operation.
Ammunition selection always involves tradeoffs.
CCI Quiet offered the lowest velocity and mildest perceived report, but it also produced the lowest calculated energy of the loads tested.
From the pistol, it generated 38 foot-pounds of energy.
For comparison:
| Ammunition | Pistol Average Velocity | Pistol Energy |
|---|---|---|
| CCI Quiet | 652 fps | 38 ft-lbs |
| CCI Suppressor | 853 fps | 73 ft-lbs |
| Federal Suppressor | 879 fps | 76 ft-lbs |
| CCI Standard Velocity | 961 fps | 82 ft-lbs |
| CCI Mini-Mag | 1,059 fps | 100 ft-lbs |
| Aguila Interceptor | 1,208 fps | 130 ft-lbs |
Additional velocity and energy are not automatically better. The right amount depends on what the shooter wants the ammunition to accomplish.
A shooter whose priority is the mildest possible report from a bolt-action rifle may view CCI Quiet’s low velocity as its greatest advantage.
A shooter using a semiautomatic pistol may place a higher priority on reliable cycling.
A shooter seeking greater velocity or energy will likely choose a different load entirely.
The important point is that no single number determines whether ammunition is appropriate.
A suppressor reduces the sound created by rapidly expanding gases leaving the muzzle.
It does not eliminate every sound associated with firing a gun.
The shooter may still hear:
This is why subsonic ammunition is often preferred for suppressed shooting. Keeping the projectile below the speed of sound removes one major source of noise.
CCI Quiet remained comfortably below typical supersonic velocity in both firearms tested. Its low velocity contributed to the mildest perceived report of the test.
However, no calibrated sound meter was used. The sound comparison was based on the shooter’s perception and should not be interpreted as a laboratory decibel ranking.
The velocity printed on an ammunition box is normally based on testing performed under the manufacturer’s conditions.
Your firearm may produce a different result.
Barrel length, chamber dimensions, temperature, ammunition lot, suppressor design, firearm condition, and other factors can affect velocity and operation.
That is why a load should be tested through the firearm in which it will actually be used.
CCI Quiet performed as an extremely low-velocity load in Tom’s rifle and pistol. It also demonstrated the practical limitation that can accompany very low-powered ammunition: the Ruger Mark IV did not cycle automatically.
Another semiautomatic firearm could behave differently, but shooters should not assume that a low-velocity load will operate every semiautomatic action reliably.
The quietest ammunition may be the best choice when minimal sound is the primary objective and the firearm does not depend on the cartridge to cycle its action.
It may not be the best choice when reliable semiautomatic function is required.
That is the practical lesson from CCI Quiet.
It performed exactly as its name suggests. It was extremely quiet compared with the other loads tested. But achieving that level of quietness required a substantial reduction in velocity and energy.
For a suppressed bolt-action rifle, that may be an acceptable or even desirable tradeoff.
For the Ruger Mark IV used in this test, it meant manually cycling the firearm between shots.
The right ammunition is therefore not simply the quietest box on the shelf.
It is the ammunition that provides the right balance of sound, function, consistency, and performance in the firearm you are actually using.
These results apply to the specific firearms, suppressor, ammunition samples, and testing conditions used. Results may vary with another firearm, barrel length, suppressor, ammunition lot, temperature, elevation, or chronograph setup.
CCI Quiet’s inability to cycle the Ruger Mark IV should not be interpreted as proof that it will fail to cycle every semiautomatic firearm. Shooters should test ammunition safely and lawfully in the firearm they intend to use.
Perceived sound was based on the shooter’s observations and was not measured using calibrated sound-testing equipment.
