Movie quiet

[Blackhawk78418]

How big of a suppressor would it take to get a subsonic round 9mm pistol, 300BO rifle movie suppressor quiet? Or is it even possible to get that quiet?

[#40Fan]

You could get close with a bolt action.

John Wick with what looked like a 4" suppressor shooting in a crowded train station and no one noticing.....isn't going to happen.

[a_canadian]

Yeah, that subway station shootout sound was pretty dang fake. A 6" x 1" tube with state-of-the-art baffles, some CCI Quiet (old type - the newer one runs a bit too hot, cranks out a couple of extra decibels), the mainspring and slide weight tuned exactly to match the cartridge for reliable cycling, and you could get things quiet enough that if the crowd were noisy-ish most people wouldn't pay attention to the shots. But those within a few steps of either guy in the scene would still notice. And at around 700fps/40fpe, it makes sense that neither shooter would react a whole lot if they actually got hit...

But like #40fan said, nah. Movie quiet is a movie fantasy. Real world suppressed gunfire is at best easy on the ears, almost pleasant to be near. And that's in the weakest cartridges. Go up to 9mm or .300blk and you're getting into 'maybe I don't need ear protection, maybe I do' territory, no matter what kinds of baffles you're using. The exception would be in something like a modern rendition of a DeLisle. Integrally suppressed with a good length and diameter baffle stack, AFTER about a 5" barrel drilled full of holes, venting into a bunch of stainless or copper mesh, all contained in about a 2" diameter by 15" long tube. Oh, and bolt action of course, with custom loads to keep them under about 900fps, as anything much over that starts getting a bit too loud.

[ECCO Machine]

With a good can, some hosts will get you there.

.22 LR is obviously the easiest, can realize sub-110 dB with a manual action integral. I have one that meters 104.9 avg. with AE subsonic.

300 blk in a manual action can also be ridiculously quiet, but since most people are running an AR, they'll never realize that potential. Likewise, 9mm is only gonna get so quiet when you still have an action opening up.



A number of lever action cartridges are ideal candidates with small bores and smaller powder capacities. The .32-20 would be a great choice. I personally like the .25-20, and with 88 gr. subsonic handloads, it's really no louder than a suppressed .22. The hammer hitting home is louder to the shooter than the report.



One of my absolute favorite hosts is my Marlin 1894 .357 mag. With 158 gr .38 loads that stay subsonic out of the 16" barrel, it's ridiculously quiet running my Phoenix IX model (9mm, 1.25" x 8"). Not quite .22 LR integral bolt action quiet, but it is literally an eye-popper/jaw dropper when people try it out.



If you fired that one in a library, it wouldn't go undetected, but people would probably think a book fell off a cart

[Historian]

The quietest .22 can was the +6 SIGMA can PTK showed on YouTube years ago ...
and sorrowfully has removed ... inferring from 'photo analysis it measured around 10" ± 1".
Estimated diameter was 1.125" ±.25".
( NRO* could not improve on this analysis )

He stated K-baffles, SS, ..." it will out last me".

It was pellet gun silent.


If anyone on this site knows the estimable PTK please see if he can repost that YouTube.
It set the standard.

If HPA ever passes a 10" version of DeadAir Mask would be made.


Happy New Year to all brethren.



* Factoid. In 1980's the Agency's name was even classified. When they
would present high altitude photo images, say of movers, they would print them
slightly out of focus to mask the true high-res capability. Now the iPhone
cameras and Leica CL 24 megapixel cameras get that resolution. Today's
technology gives freakishly higher resolution via nonlinear wave-propagation-through
-random-media analysis. Star Trek.

[a_canadian]

Are you referring to this one?
https://youtu.be/fyBNJ_31uQc
Pretty darn quiet, even allowing for the inevitable camera microphone cutting out on every shot. It's sort of funny how we quiet plinking enthusiasts have to learn to 'hear through' distortions such as those generated by well-intentioned microphone designers.

[Capt. Link.]

"How big of a suppressor would it take to get a subsonic round 9mm pistol, 300BO rifle movie suppressor quiet? Or is it even possible to get that quiet?"

Most of the big bore integral rifles ie: .44 .45 caliber have a supposed sweet spot of around 50 ci internal volume. I would think that a similar or lesser volume would work on 9mm or 300Blk.

The problem is that volume alone is not the answer.Longer suppressors tend to be quieter per ci than fatter ones of the same volume.Baffles and spacing choice can be quieter than more ci.Velocity also makes a huge difference as dose caliber and bullet choice.I'm not even going to speak about the use of ablatives that will shrink suppressor size and db losses.Its a difficult question as technology makes suppressors smaller and quieter every day.

So much great information from many of our OPS. I like in particular the thought of a suppressed 25-20 ECCO! Historian I remember that suppressor,huge but quiet.

The best .22 pistol I've seen tested measured 106 db close to 30 years ago by a UN-named three letter agency....
Best .45acp buzz gun used a CO2 flushed suppressor at 115 db same time frame.

This suppressor is stunning in 300blk: https://youtu.be/z17UQUYzPhQ I would love to know what they did?

[alordnapa]

Yes, you can get "movie quiet" suppression in a relatively small package. I suppose a lot depends on your expectations. You will have to be willing to put up with a can that is both wet and wiped. You can achieve the highest possible suppression, with the possible exception of captured -bolt ammunition, with old-school technology...at least for a few rounds. How many spies will you have to shoot?

[Dunkman]

This suppressor is stunning in 300blk: https://youtu.be/z17UQUYzPhQ I would love to know what they did?

That suppressor is impressive. I did some snooping. Forgive my ignorance this is my first post, but I couldn’t get the images to post. Here is an Imgur album.

https://imgur.com/a/F7CWT9W

[Historian]

Are you referring to this one?
https://youtu.be/fyBNJ_31uQc
Pretty darn quiet, even allowing for the inevitable camera microphone cutting out on every shot. It's sort of funny how we quiet plinking enthusiasts have to learn to 'hear through' distortions such as those generated by well-intentioned microphone designers.

YES!!!

Many thanks, my friend, I have missed being able to visit it and dream of HPA's
passage so I can build one ...and commission my Balkan 'cousin'* to make
an 'artillery Luger' length 10" Mask HD for kicks.

A most Happy New Year to You!


* Mike, have you ever made a 10" version of HD and measured its value?
Cost no object.
Old 1940's adage to young mind full of mush, "A fool and his money are
soon parted." "Et ici je suis insensé," ... as he jumps up in back to get
attention.

[Blackhawk78418]

Thanks for all the input everyone and that VOX video is what got me started. You cant hear that 50yrds away with a breeze blowing. But on other videos it doesnt sound like that. I'm sure some ppl edit their video for sound.

[Benzy2]

I’m not sure what went on in that VOX video. I don’t think they did anything nefarious in their taping/editing but it also isn’t a repeatable result. I know you won’t get close to that with a semiauto but it was still a unique result.

The biggest solution to lower noise is first a locked action (bolt/lever/single shot) and second is good, quiet ammo. It’s amazing how much difference ammo makes. You’d think subsonic is all about the same but powder differences and velocity make a huge impact on noise. There is a thread on here in the reloading forum that is a great read about noise levels relative to velocity.

Obviously from there silencer design makes a huge difference but a lot of them will make quiet ammo in a non autoloading firearm sound great.