# Are silencers really as silent as in the movies? **URL:** \ **Category:** Factual Questions\ **Created:** [October 30, 2002, 9:51pm UTC](https://boards.straightdope.com/t/are-silencers-really-as-silent-as-in-the-movies/134597 "2002-10-30T21:51:19Z")\ **Posts on this page:** 6\ **Page:** 2
**Author:** ![Kalashnikov](https://avatars.discourse-cdn.com/v4/letter/k/2bfe46/32.png) [@Kalashnikov](https://boards.straightdope.com/u/Kalashnikov)\ **Post date:** [October 31, 2002, 7:53pm UTC](https://boards.straightdope.com/t/are-silencers-really-as-silent-as-in-the-movies/134597/21 "2002-10-31T19:53:49Z")
Suppressors are not illegal by federal law, nor by most states’ laws. They are regulated by the National Firearms Act, the same law that control machine guns etc., and in fact they are classified as firearms by that law. I’m trying to find a direct link at the ATF site but it’s responding very slowly today… anyway its somewhere reachable from [http://atf.treas.gov/firearms/nfa/index.htm](http://atf.treas.gov/firearms/nfa/index.htm) They must be registered to the owner, and to do this you have to pass a special background check, submit fingerprints and photos, get the approval of your local chief of police, pay a special tax, agree to allow the ATF to search your house at any time, etc. etc. etc. This isn’t exactly easy, but it isn’t impossibly hard either. I know several people who own silencers or other NFA firearms. ---
**Author:** ![Padeye](https://avatars.discourse-cdn.com/v4/letter/p/a9a28c/32.png) [@Padeye](https://boards.straightdope.com/u/Padeye)\ **Post date:** [October 31, 2002, 7:55pm UTC](https://boards.straightdope.com/t/are-silencers-really-as-silent-as-in-the-movies/134597/22 "2002-10-31T19:55:42Z")
> [@](#): > > \*Originally posted by King Nifty \* > \*\*Is anyone going to answer my question? Is the sound silencers make in the movies (“peeer!!”) bullshit or not?? \*\* I have never heard a suppressed weapon that sounds like the _type_ of sound the Foley artists dubs into most movies. On a few occasions I have heard a realistic suppressor sound cut this is the exception. In real life the _level_ of the sound can be louder than the movie sound to near silent. ---
**Author:** ![King\_Nifty](https://avatars.discourse-cdn.com/v4/letter/k/f9ae1b/32.png) [@King\_Nifty](https://boards.straightdope.com/u/King_Nifty)\ **Post date:** [October 31, 2002, 9:27pm UTC](https://boards.straightdope.com/t/are-silencers-really-as-silent-as-in-the-movies/134597/23 "2002-10-31T21:27:32Z")
Thanks Padeye! ---
**Author:** ![samarm](https://avatars.discourse-cdn.com/v4/letter/s/4da419/32.png) [@samarm](https://boards.straightdope.com/u/samarm)\ **Post date:** [November 1, 2002, 12:13am UTC](https://boards.straightdope.com/t/are-silencers-really-as-silent-as-in-the-movies/134597/24 "2002-11-01T00:13:57Z")
A related note (minor hijack): Some semi-automatic pistols have a mechanism that allows the slide to be locked in place. This means that when the trigger is pulled, the only moving part on the pistol is the hammer striking the primer on the cartridge. This further depresses sound, when used in conjuction with a silencer. It does however mean that the next round is not automatically chambered. From what I have heard, it may also mean there is slightly more kick-back than usual, as the slide is unable to take any of the energy from the recoil. ---
**Author:** ![dsconrad](https://avatars.discourse-cdn.com/v4/letter/d/58f4c7/32.png) [@dsconrad](https://boards.straightdope.com/u/dsconrad)\ **Post date:** [November 1, 2002, 6:31am UTC](https://boards.straightdope.com/t/are-silencers-really-as-silent-as-in-the-movies/134597/25 "2002-11-01T06:31:39Z")
Here’s a site that has a movie of some guys shooting silenced mp5s. [http://www.hkpro.com/mp5sd.htm](http://www.hkpro.com/mp5sd.htm) BTW, some supressors do “slow” the bullet… the mp5sd has an integral supressor with the barrel which allows a supersonic bullet to slow to subsonic speeds before it leaves the muzzle. Suppressors do not work on supersonic bullets… they reduce or eliminate muzzle flash and muzzle blast, but not the sound made by a supersonic bullet. However, it’s a lot more difficult to tell where a shot is coming from when you can’t see the flash, and the only noise you hear is generated by the bullet as it passes by (as pointed out above). ---
**Author:** ![smiling\_bandit](https://avatars.discourse-cdn.com/v4/letter/s/e9a140/32.png) [@smiling\_bandit](https://boards.straightdope.com/u/smiling_bandit)\ **Post date:** [November 1, 2002, 2:29pm UTC](https://boards.straightdope.com/t/are-silencers-really-as-silent-as-in-the-movies/134597/26 "2002-11-01T14:29:12Z")
[quote] Thats the idea, I believe with silencers- they slow the bullet to subsonic speeds to eliminate the little sonic boom generated by the bullet. [quote] To my understanding, most silencers do the largest part of their work slowing the exit of hot gas from the barrel, not by slowing the bullet. Going from supersonic to… not supoersonic wouldn’t help _that_ much, I think. [Previous page](https://boards.straightdope.com/t/are-silencers-really-as-silent-as-in-the-movies/134597.md?page=1)