How do Silencers Work and the Science Behind them

www.ModernPawnAndGuns.com
modernpawnandguns

[@hoosierdaddy2308]

Great video.I'm 55, and in the early 80s I worked for a specialized ammo company that made ammo for military and police. We would test some calibers in full autos with suppressors such as the Mac 10, etc. I remember the packing and replacing wipes..:-)

[@virgilebeats3041]

Amazing vid, the fact that you went for the equation makes it so much easier to understand and deduce the rest by yourself. Thanks !

[@herzali]

Man you are a good teacher! You made it very simple and clear thanks.

[@STBRetired1]

EXCELLENT - in spite of some of the negative comments posted. The only remaining question I had was does the direction or angle of the baffles have any significant effect on noise suppression. But, I suspect that may be answered in your next video "Suppressor Design Types". Thanks for taking the time to inform us. I'm also thinking that gun suppressors could be a lot more effective if everyone wasn't so obsessed with miniaturization. Is it really that more uncomfortable to go from a 1" diameter suppressor to an 1.5" or 1.75" unit? With the bigger size, you could have a suppressor within a suppressor to do a better job of expanding and cooling the gases. Hell, I wonder if you could pack between the inner and outer shells with a copper heat conductive paste to improve cooling as they do with engine blocks to conduct heat away.

[@felimraftery4141]

Thank you so much. You posted a video 6 years and 6 months ago when I was in 10th grade playing MW3 all the time. Now I'm a Senior in College and I have to design an experiment about what factors most affect the performance of a silencer. Those twenty minutes it took you to make edit and post this video just saved me multiple days of research. Legend.

[@modernpawn]

Thanks for the kind words!

[@koonsickgreen6272]

so well versed in computer graphics, audio, and physics. And the way you draw.. modern day Leonardo DaVinci

[@modernpawn]

Thanks for the kind words and thanks for watching.

[@beshbarmax]

I would have given more likes to your video if I could. Finally a sensible explanation of the topic to the laymen like me. Thank you!

[@markletts2000]

I watched another version, with CGI etc on this topic,and after 5 min he still hadn't told me anything of any relevance, in fact after19 seconds I'd got more information from you.. Excellent, well explained video ..respect ,thank you!

[@modernpawn]

No, the bullet actually ends up with a slightly HIGH velocity when a suppressor is used. The pressure is the same as the bullet travels down the barrel. The bullet is under the same force as normal, when the bullet exits the barrel, the gas behind it enters suppressor where it has its pressure reduce. At this point the bullet is already at velocity and passes through the baffles. The gas is then 'trapped' by the suppressor so that it exits the suppressor at a lower pressure.

[@Niphatorn]

That's exactly what you explained, graphically, in your video.👍 Someone was not paying attention.🤔

[@dmpruitt7436]

Could a suppressor or something similar to a suppressor be used to lower the noise level of a portable generator ? I know exhaust muffler's will obviously but they seem to choke the engine.

[@Name-ps9fx]

A bit of trivia, seems like I heard it from a book describing how silencers work... The ratio of the volume of the suppressor : volume of barrel should be around 20:1. Ex.: A 5.56 w/a 16” barrel has about .785 cu. inches of volume...x20 = 15.7 cu. inches for the suppressor, which roughly works out to 2” dia. x 5” length (a little larger if one accounts for the volume taken up by the baffles). Just a suggestion if someone is interested in where to start in their calculations...

[@JonBurnsArt]

thank you, sir. action type, pressure, bullet velocity: all things considered = genius

[@saeidsharifi2250]

Hi. when I have a 9mm caliber, what is the diameter of center hole of suppressor.

[@chiefkyle1098]

In other words, if you had a suppressor with baffles full of dry ice, it would sound like a mouse farting.

[@4thidvetastor886]

Good job with explaining that their young man thank you so much. You kept it simple and direct. The water in the suppressors was confusing me until you explained the heat dissipation. Thanks again.

[@kirkjohnson9353]

I wonder why there are not versions of suppressor that have small holes along the can to relieve pressure before the final exit? Wouldn't some small holes let out some pressure and help ?

[@quipayano962]

Does it also applies to air rifles with lower velocity pellets? Also, does the silencer sacrifice the velocity of the bullet?

[@jizzmonkey9679]

They can sometimes increase the velocity of a bullet, they can also effect accuracy as the harmonics of the barrel change , longer barrel length seems to be affected the worst.

[@georgessemaan5617]

Simple explanation in simple way for knowledge "after 8 years from posting this video" = (this was the only video that I understood about silencer after watching most youtube videos) ... All do respect ‼️ *Can I made a home made silencer for a shotgun ⁉️ Thank you in advance...

[@lenchongloi5881]

While applying silencer do we gain more or less recoi?

[@mdk2066]

Very good video. You have excellent teaching skills. Editing to save time was good, as well.

[@stormypole]

What if we make the baffles upside down .... or say make the first 2 baffles in reverse and the rest in normal position... Cos the angle of shock wave makes such an angle ... would it reduce the Db???

[@d-unit-outdoors]

Excellent video

[@eddyflo2978]

Need a updated video with all the new models / types of suppressors out there

[@yimmeistaryimmeistar7239]

Question. Is it Essentially the gradient of pressure reduction which generates the sound that can be suppressed. I.e. a high gradient or pressure reduction of 30000psig to 0psig in a half second will make more noise than 30000psig to 0psig in 1second. The suppressor extends the time taken for the high pressure to reduce to atmospheric. The heat factor (temperature in absolute terms i.e. in Kelvins), can be tested by using a high pressure "noble" gas like nitrgen at ambient and expanding it in the same manor. I.e. suppressed and unsuppressed. And record the decibels? Apologies for length of comment / question.

[@manfredrichthofen2494]

...shhhhh 🤫, l just subscribed.. I wish my physics teacher was as articulate and simple as the way you explained things..

[@modernpawn]

No, heavy duty snipers often use suppressors. 50BMG semiautos are hard to suppress becuase they tend to beat up the rifle, BUT Barrett has designed a suppressor designated for the M107. AAC makes one as well. The suppressor does not effect the range of the bullet nor does it cause a reduction in exit velocity.

[@nicedward7544]

It often improves accuracy on precision rifles by reducing turbulence before kicking it all the way out into freedom

[@royd7984]

Very good video and explanation than even I understood. Thanks

[@geek1989]

I've seen commercial suppressors with holes along them. Do these use the heat sink method?

[@modernpawn]

action noise is pretty much always inside hearing safe. Although back pressure or gas coming out of the action can be a bit loud. It has little to do with the suppressor, and mainly based on the host weapon.

[@CaptainJim]

Great video, I hope to get my SOT license soon. Your formulas are right on target. Mechanical Engineer

[@CaptainJim]

Great Video...

[@tboneproductions2453]

Basically, this also explains loud flatulence vs the silent killer. Fewer molecules = suppressed sound. Also why the colder the temperature, the less oderous

[@SynS7ven]

Anyone interested in a better understanding can google "thermodynamics throttle". Not only will you better understand how it suppresses sound, you will also see it has other affects like reducing recoil. Of course in practical terms, you have to think of the system as a whole to really understand how this will "feel".

[@B1rd0fpr3y]

Just one sideone. The sound from popping a balloon comes from the contraction of its rubber surface, and not from the air inside.

[@aw11roman]

I would have thought that there is a complex system of compressions and rarefactions that travels up and back between the end of the round and the firing chamber as the round moves up the barrel. Once it leaves the barrel, these sound waves are also able to leave the muzzle behind the round. So the purpose of packing (particularly fibreglass), is to acoustically absorb these sound waves. And although the acoustic energy of these sound waves is ultimately converted to heat by the packing (similar to the method via which car mufflers operate), it is technically incorrect to call it a "heatsink effect", which implies heat dissipation via radiation. Good video though

[@hansdown5508]

Great into to suppressors and looking forward to your next video

[@winstonsmiths2449]

I am looking for a design that uses modified Tesla Valve type design. Do not know if gases can be slowed down like fluids in a can. A Tesla valve would cause an explosion or at least extremely high pressures inside the can, so the mods would have to allow for escape of gas. Whether that could be along the length of the can or just toward the front. Curiosity here.

[@MrRockstar1968]

What do you mean by action?

[@EastendBillythekid]

Oustanding titorial.. Awsome man just awsome Thank you.. Can we build a release tube shaft for the bullet to travel threw but collect the gas = noise from it into a muffled chamber?

[@coraygc11]

Great explanation. Thanks for the educating!

[@Gabryhunter]

This was very interesting! :D

[@Za7a7aZ]

What about the faster than sound boom...is the function of a silencer also to reduce speed of a bullit below the speed of sound?

[@tonyromano6220]

Ash Richards no

[@Za7a7aZ]

@@tonyromano6220 I don't understand. I assume you want to keep things quiet with a silencer

[@JustOneMoreTaskMom]

​@Za7a7aZ subsonic ammo is used to keep from hitting the sound barrier. A suppresor doesn't decrease the bullet velocity in most cases and can sometimes increase it, albeit not enough to matter. One thing to note is that the sound of a bullet going through the sound barrier and the sound of a gun firing are 2 different sounds. At a long distance you will hear the bullet way before you hear the sound of it being shot. A bullet hitting that sound barrier does not give away the shooters location as much as the sound of the gunshot itself.

[@tracyhjelmstad7061]

Use lithium grease in a wet "can" to decrease the temperature.

[@HiTechDiver]

Very informative; breaks it down into the details

Thanks. It was a great explanation.

[@Pukovnik141]

modernpawn You said you will do a wet "can" (suppressor) video, and what can we use in it. Could you direct me to that video, or you didn't make it jet?

[@Jack-ny7kn]

If only it were that simple! Surprisingly, increasing volume doesn't always work. It can actually make the silencer louder. The main challenge in any suppressor design is pulling the laminar column of gas away from its path of least resistance and somehow getting it to voluntarily go inside the baffles instead of out the bore. Since you can't have anything directly in its path, as it would strike the bullet, the only way you have to control it is pressure differentials inside the can. That's why all successful designs have some kind of baffle clips. It creates an area of low pressure, which causes the laminar column to bend and get trapped in the baffle stack. Then it's like a pileup on the interstate, so the gas exiting the silencer is less focused. Getting that column to bend and drive itself into the baffles has a lot to do with the length of the silencer.

[@eddyflo2978]

Please expand on this with a actual video!

[@Jack-ny7kn]

@@eddyflo2978 Unfortunately I don't have the time or equipment to make that happen, but you can see the proof in the pudding based on what's out there. Just google like silencer cuataways or something along those lines. You'll notice that the cans with the most aggressive clipping tend to be the quietest. You'll also notice there's no correlation between bigger cans and quieter ones. Once the can has enough volume overall, which depends on caliber, going bigger doesn't help. So like for example you'll see 223 cans are almost always around 1.5x7. That will vary somewhat based on materials used and what's going on inside the can (like a coaxial chamber might make it fatter because you have two walls and a bunch of dead spaces). Then for the really big magnums you'll see the diameters go up to like 2 inches, and lengths in excess of 10 inches, because they have to handle that crazy volume of gas, since those rounds have a ton of powder behind them. Or full auto rated cans will have to have more volume because the pressure doesn't have time to drop back to ambient in between shots, so you get a buildup.

[@TacticalTerry]

Makes a lot of sense the way you have explained it. Thanks!

[@connorhannigan4310]

So then the suppressor would take away from the speed and damage of the bullet?

[@modernpawn]

I am familiar with the proper term, suppressor. But that average person will search for the word silencer. The slang silencer (or can) is often used even by the people that make them, sell them, etc. Anyways, thanks for the ball busting. No hard feelings :) Keep watching.

[@GarthKlaus]

modernpawn Silencer is also the legal term, though suppressor is more descriptive.

[@tyronesterling4158]

Do I need to fill out the Form 1 before I purchase a suppressor, or vise versa?

[@ctsteve1967]

You do not need to do anything at all

[@aan47axf17]

If you modify it, you need!

[@vectorcide]

Best explanation Ive heard...

[@markletts2000]

I checked out several vids,and this is the one you want if your thinking of fabricateing a suppressor,well explained,lots of diagrams,idiot proof,just what I needed...I made one out of a £3,kids Ali telescope,sleeved over the existing one with plastic baffles,12" long now,halved the sound again,and it looks the bollocks!(22 German air rifle,in England )

[@Swirlyy21]

Great explanation mannnn thaaaanks

[@aboazam1990]

just wondering, isn't reducing the pressure will reduce the force that will push the bullet. if that's true the distance the bullet will travel will be reduced when using a silencer. right?

[@andyelwood7123]

Ahmed AL-Qatta TAKE a bolt push it in THE end of your barrel and weld it, then pull the trigger as fast as possible. Does THAT make sense. Bro

[@jeffreystroman2811]

@@andyelwood7123 what?? Do you even know what your talking about? Anyway, any barrel left intact with the device added will almost certainly add a tiny bit of muzzle energy. Rare instances of turbulent issues and phase anamoly can occur, often during trial and error testing. Different approaches can and do lower muzzle energy, or velocity for you pedestrians.

[@lylestavast7652]

no.

[@modernpawn]

Briefly: They add weight and size to guns They make guns run dirtier They can in some cases cause malfunctions They get hot and on rifles I mean HOT. Other than that, any down side is well worth the decrease in sound and recoil.

[@douglasfletcher718]

Thank you for not uttering the idiotic phrase "it traps the gases". Too many people believe that shit and it's just not true. I do have one point of contention and the otherwise brilliant explanation. You don't mention Bernoulli's principle, and where turbulent flow of a liquid does increase the thermal exchange rate, the constrictions actually do more to reduce the pressure than eliminate temperature.

[@thafirstborn2550]

Yo u had me off da rip when u said " hey guys resdy 4 some high tech comp graphics" thing Foreal63💯

[@modernpawn]

no offense, but if your penis has baffles and threads, you need to call a doctor.

[@jedikilla10101]

Dude I was so confused as to why it doesn’t turn or mess with a bullets direction. Like how come the bullet doesn’t change directions when it’s going through the silencer chambers

[@kurthasseler277]

boyles law, sums it up quick. nice vid.

[@coreyg7575]

subbed for the great artistry!! impressed

[@myronm9496]

Good explanation on how suppressors work. However, as air is considered an ideal gas, this combustion reaction will not. The reaction products will contain CO2 and water vapor, neither of which are ideal gases. For elementary purposes, CO2 can be considered an ideal gas but at these extreme temperature/pressures, will have a large percent error if you tried to perform a thermodynamic calculation; I think you would need to use an energy balance to calculate pressures. Don’t have my thermo book, but this situation is a little more dynamic than calculating flows and heat transfer.

[@andrewstamm9941]

I used brass tubes with holes drilled through it. I surrounded the tube with aspestice for the exit out of barrel. Then used rubber baffles for the last 5 inches. It worked. The 22 jammed often. However I learned from a friend that you're not supposed to build that kind of thing. Which is bullshit I target shoot!!!! Not kill.

[@eddyflo2978]

The ATF wants your location 🤣🤣🤣

[@413westernmassbornjp6]

Higher the pressure the louder the pop n father it's gonna go. Nice lil science lesson lol

[@peter81083]

loved thew computer graphics, but i can hook you up with a vid card thatll make em a bit sharper, hehe... i LOVE how you mention the expansion/coolling of gas, that and barrel twist are the 2 things NO novice takes into consideration. just wanna say as far as subsonic goes, you can... aside from dropping grain weight, increase projectile weight ;) ....and of course, white lithium on the internals... ;)

[@StevenSchoolAlchemy]

Greetings fellow KZbinrs

[@TXBIGMIKE]

good job

[@dravifo6762]

Why don't suppressors have cooling fins?

[@bigwally1718]

Not needed. Suppressors operate in free convection.

[@leonda4817]

Youd could make them that way, but nobody ever did. SIlencers get worse the hotter they are

[@orion2250]

Gonna have to go by soon!

[@D_theRN]

cool stuff malak...

[@thor595]

Good videos keep em coming

[@user-qt8zt6zg6w]

Would have ben hilarious if you would have yelled BANG without breaking character while you were explaining why guns are loud

[@felurianmasters4369]

Lol, you know what the second drawing looks like right

[@kheirzcass5773]

Thank you

[@aan47axf17]

Basically silencers are the actual name the person who made gave the thing; as the aim of it was to “silence” the gunshot. But because they don’t actually “silence” the shot they just “suppress” it, people called it suppressors

[@gregorbegger9291]

They’re called both. They can silence the noise, it just depends on how big the bullets are and how much pressure is in the device

[@modernpawn]

Thanks for watching!

[@matt1267]

best penis drawing to date, also you forgot about thermal expansion of the gas (delta L/L=alpha L deltaT). Ideal gas law does not work correctly without using the equation first to find T1 and T2. At about minute 5:30, your entire segment becomes invalid. Gas will expand based on its rate of thermal equivalence. You could literally have a silencer the size of the moon, and if the temperature is too high, it will not suppress to the desired effect. P2 cannot be calculated without knowing delta T....

[@pepeman3099]

COOOOLLLLLLL

[@jeffreystroman2811]

Old electronics guy here, alright, not "old" but you know, recently began to self teach Bernoullis law as I almost can't believe I ignored it for so long (again, relative) any chance the "R" is what is known as the Reynolds number? Not cheating, checking myself.

[@modernpawn]

Like the Knights Armament? That is normally a heat shield that is welded to the outside, to help from burning yourself and to held dissipate heat.

[@I-Love-Taylor-Swift]

What if the bullet hits the edge of the baffles?

[@assamrifle1]

what are the disadvantages of using a Silencers ???

[@gespecht]

You keep your hearing longer. Annoying sounds will bother you for more years.

[@jeffreystroman2811]

Chasing off a mugger or rapist by firing Into the air. This may seem like a joke but trust me, it's an issue.

[@BrokenIceShards]

So.Is this why heavy duty snipers like the Barrett are not encouraged to use suppressors as it shall defeat it's purpose at extremely long range and damage?

[@shakalpb1164]

hehe Physical Chemistry I meet you again my friend

[@aboazam1990]

Got it .. Thanks

[@blackriflex39]

A car muffler basically. You made it easy

[@PrizrenVEVO]

Dat drawing..

[@matthewsadgrove2214]

Nice vid

[@Name-ps9fx]

You can drop a lit "lady finger" firecracker into a barrel or pipe, and you can hear how loud those gases are. Quite shocking if you're used to lady fingers going off in the open air....

[@ranaemad684]

he can explain it in multiple ways he knows what he is talking about he can explain it to ppl who doesn't have any idea about it in simple way and for ppl who brain works with numbers of physics. .wow

[@fordnut4914]

Thats a naughty looking 🔫 😂🤣

[@iamt_tl]

why do this physics teacher at a gun shop has so little views?

[@mrPauljacob]

Lower the pressure. Got it

[@nelsonstrickland1069]

So.......suppressors do not effect bullet exit speed....AWESOME !!!.

[@ctsteve1967]

Why wold it?

[@jeffreystroman2811]

Let's be precise as that's what it's all about. The particular one shown here, yes. Another technique (among countless) is an internally suppressed. Relief ports in the barrel dump pressure to lower velocity to subsonic, effectively shortining the effective length. One of my newer ideas is interacting Chambers that play with phase shift to cancel themselves out. Some car mufflers do this, flowmaster I'm looking at you, BMW among others

[@modernpawn]

thanks for watching.

[@robbiekipping1124]

Why risk going to jail over 200 bucks?

[@C_DOG]

I am the 172,662nd person to start laughing 15 seconds into this video.

[@ctsteve1967]

yes sir you are, What he is saying is true but OMG

[@anselmoalliegro460]

This should work: Fast and effective baffles for a silencer may be created from a relative stiff 1 ½ wide flat strip of spring steel. 1. The strip of spring steal is folded back and forth to create an accordion. 2. On a grinder, the compresses metal accordion is perfectly rounded along two edges. 3. On a drill, once the two edges are rounded, a hole larger than the caliber to be used is drilled in the middle of the compressed accordion. 4. The accordion is now pulled and inserted in an aluminum tube. It must fit smugly as if paper dolls. The tube has a cap with an exit hole in one end and a barrel attachment at the other end. 5. When a bullet is fired through the center the accordion acts as baffles. The gas is delayed and compresses the coil taking up further energy. The corrugated steel accordion behaves as a spring inside the tube.

[@henryhenry903]

Anselmo Alliegro we did it with thick stainless washers in a press to give them a bowl shape and machined a solid rod with detent grooves and then pressed them in until they snapped into the grooves. Cut threads with the lathe and it works awesome

[@noretreat2074]

Henry Henry.... your way lacks the compression of the baffles (much like the closing of a spring) which will take some pressure from the gases. (provided I picture his design correctly). All Black Rifles Matter

[@ColdPotato]

The only science is how they can maintain these outrageous prices.

[@marksalot655]

Wow. From now on I’ll go to a pawn shop for all my scientific analytical experiments. Who needs pee-ache-Dee scientists to provide facts. The pawn shops have it all covered in in-depth detail. 👍👍🤔🤔😳🤔🤔😎😎 🤣🤣🤣🤣🤣🤣🤣🤣🤣

[@Name-ps9fx]

Marks Alot Was there an error in the video? Or are you just dismissing the info because of who presented it?