There are a lot of myths about suppressors out there. Fortunately, we have United States Marine Corps Gunner Christian Wade to set the record straight.
After the Marines started experimenting with suppressing every weapon in an infantry battalion last year, many people understandably had questions and concerns about what the Corps was doing. In response to all the questions he was getting about the subject, Gunner Wade decided to make a video busting some common myths about suppressors.
Not to be confused with a "Gunny", which is a noncommissioned Marine Corps rank, a "Gunner" is a Chief Warrant Officer who is a weapons specialist and is skilled in the tactical employment of all the weapons the Marines use. Gunner Christian Wade is a Chief Warrant Officer 5 and is the Gunner for the 2nd Marine Division, literally making him an expert on small arms and their employment. I don't know about you, but I can't think of a better source for reliable information regarding the employment of suppressors by the Marine Corps and busting some common suppressor myths than him.
So there you have it straight from a guy who really knows what he's talking about: suppressors do not adversely impact the lethality of a weapon when it uses standard ammunition. Truth be told, this is probably a myth about suppressors that comes from people playing too much Call of Duty, which imposes a damage penalty on suppressed weapons.
The fact that some suppressor users also shoot sub-sonic ammunition, which actually does reduce the muzzle velocity and therefore effective range and lethality of a weapon, in order to further reduce it's noise signature, confuses the issue even more.
There are some disadvantages of suppressors: they're expensive, they need to be maintained, and they increase the overall length of the weapon. However, as long as you use the same ammunition, a suppressor doesn't significantly change the muzzle velocity of a weapon.