Silencers, Moderators or Suppressors call them what you will, the term conjures up images of secret agents, assassins, commando raids and poachers. In fact the possible applications for such devices are far more general and may greatly benefit the modern hunter or soldier.
Several factors contribute to the noise of a firearm, but the most noticeable are the muzzle blast and the supersonic crack of the bullet breaking the sound barrier. Suppressors can be broadly divided into two groups those that try to remove the supersonic crack and those that don't. The former systems try to reduce the round velocity, either by "friction wipes" or by bleeding off some of the propelling gas. The second form of suppressor only deal with the muzzle blast and need to be used with sub-sonic ammo if supersonic crack is to be avoided. Some rounds such as the .25ACP, .32ACP, .380/9mmK and .45ACP are subsonic in their standard loadings. Most other rounds need especially produced sub-sonic loads.
This begs the question:-
"What happens if you fire a supersonic round from a weapon with a suppressor that only deals with muzzle blast?"
The answer is that the bullet still breaks the sound barrier but there is no muzzle blast. In practical terms this means the target can hear that it is being shot at, but has more difficulty determining where from. Using a supersonic/normal velocity round in a suppressed weapon has several advantages, and this is the topic of the rest of this article.
Firstly, the weapon has the same range and terminal effects as an unsuppressed weapon.
As well as reducing the noise of the muzzle blast, the suppressor also hides any muzzle flash. Because the muzzle blast is contained, firing when in a prone position does not throw up any dust or debris. In short, not only is it harder to hear where the shooter is, it is also harder to see him!
Suppressors also have a recoil reducing effect. This is partially due to gas pressure against the end cap, but also due to reduced velocity of the gas leaving the suppressor muzzle. This phenomenon is explained better here. Unlike a muzzle brake, the suppressor does not throw gases out to the side, to the detriment and discomfort of companions. On certain weapons it has been noticed that the fitting of a suppressor reduces muzzle flip and climb when firing.
For some weapons the use of a suppressor improves accuracy, since the bullet emerging from the gun receives less buffering from turbulent gases.
The reduced noise level of firing a suppressed weapon has another, often unappreciated advantage. It is well known that firing can produce temporary and permanent reductions in hearing, which is why shooters wear ear protectors when possible. When hunting or in combat this is often not practical, but firing will also reduce your hearing efficiency under the conditions when you need your senses at an optimum. Using a suppressed weapon helps protect a shooter's hearing. One of the reasons that many SWAT teams use suppressed SMGs is to reduce the sound hazards from gunfire in confined spaces, such as building interiors.
In summary, a suppressed firearm with supersonic ammunition has less blast and flash, less recoil and protects the shooter from hearing damage. These benefits come without any reduction in range, accuracy or lethality.
An interesting side benefit of Suppressors is that for many individuals it is easier for them to learn the fundamentals of marksmanship without the distraction of noise and muzzle blast.
Suppressed Guns for Hunters. The main advantage for a hunter in using a suppressed weapon is that it helps protect his hearing. A dog's hearing is far more sensitive than a man's, so using a suppressed rifle will also protect the health of your hunting dogs too. Reduced firing noise will spook the local animals less and not disturb the peace and quiet of any humans in the area. Since hunting rifles are "often carried, occasionally fired" many hunters wisely select lightweight weapons. The recoil reducing effects of the suppressor may be appreciated for such arms. In the US acquiring a suppressed fire arm requires a lot of red tape and has a $200 tax fee. This expense should be balanced against the value you place on the preservation of your hearing.
Suppressed Guns for Infantry. Here we might have a problem, since many military minds will associate a silencer with a clandestine weapon or one of reduced performance. This may be the time to prudently re-market the device by calling it a "Blast Suppressor", even though strictly speaking it is a Moderator.
The most useful class of weapons to suppress are actually one that few people associate with suppressed firing :- GPMGs and SAWs. Machine guns form the bulk of a unit's firepower, but also create alot of noise, dust and flash. Reducing these factors will make it harder for a foe to locate and neutralize a machine gunner. One can imagine the frustration and loss of morale that a foe will feel as men are injured and pinned down by machine guns they cannot find. The reduction in firing noise will also spare the ears of gunners firing fully automatic for long periods. Suppressors especially designed for use on Machine guns are shown here. The outside of a machine gun suppressor might be fluted for strength and improved cooling. For economy reasons if no other reason I think we are unlikely to see the widescale issue of suppressors for assault rifles. A suppressed rifle cannot be used with any of the current models of rifle grenade. This is not a major drawback if the rifle has a M203 type launcher or can use disposable grenade launchers. Suppressed weapons may be used by Hostage Rescue teams and Long Range Recon units. Grenades suitable for use with suppressed assault rifles could be developed. These will probably have a tail ring or fins that clip around the suppressor. Another objection to suppressors on rifles is that they may make bayonet use impossible. Bayonets that fit to suppressors are possible, but I suggest a folding bayonet attached to the suppressor. By having the hinge of the bayonet on the suppressor rather than back at the bayonet lug a more handy and effective bayonet can be mounted. Rifle grenades could be constructed so that they are not hindered by the folded bayonet, or may use the bayonet as another anchor point.
Suppressors for Big Guns. Large calibre sniping and anti-material rifles have gained popularity in the last few years. At least one company has produced a suppressor system for .50 calibre rifles in an attempt to reduce muzzle flash and blast. I've suggested in other articles that weapons such as the South African NTW 20 could be useful for both anti-armour platoons and for stand off attack by Special Forces. This weapon used 14.5mm rounds for long range shooting and 20mm cannon shells for maximum target effect. A blast and recoil suppression system for both these barrels would be very useful. I've also suggested a saboted long range bullet for the 20mm barrel so that only one barrel type is needed. I've also floated the idea that AMRs could fire their own rifle grenades for target illumination and other purposes. Since these will be somewhat different from assault rifle launched grenades a practical approach may be for the end of the suppressor to be formed into a sort of cup-discharger.