As a rebuttal to
The_Custodian's otherwise excellent wu, there is at least one truly silenced firearm.
Heckler and Koch makes a variant of their venerable
MP5 named the
MP5SD, with the sd standing for supressed. I have fired this gun on two occasions. The only audible noise that this gun produces is the cycling of the
bolt while firing. This firearm is quite frightening to use, as you have quite a shock as to just how quiet it is. I apologize for this being the only firearm I know of which is truly silent. If anyone knows of any others, please let me and
The_Custodian know.
I apologize for any typos that slipped through-Band-Aids suck