Suppressors Silencer design

[Ranb]

I had a request for silencer designs suitable to make on a hobby lathe, so I thought I would post a few of my drawings. For those live in the USA so the only way to make a silencer here without a license is to submit the ATF form 1 (Application to Make and Register a Firearm). The forms can be ordered from the ATF homepage, but it takes a few months to get them as they are running behind since the great demand on their time caused by the last election. The ATF form 1 available from http://www.titleii.com/TitleII.com/Welcome.html is the old revision. I heard they are still accepting them until the new revision is available online at the ATF homepage. I sent one in a few weeks ago, hopefully if it is rejected, they will send me the new forms to fill out and send in again.

It is important to remember that you can not start to make parts until the ATF form 1 is returned approved with the canceled $200 tax stamp attached. Once the silencer is made, parts can not be replaced, the bore changed or the length increased by the person it is registered to, unless another $200 tax is paid or it is sent to an SOT class 2 for repairs. It is also illegal to have replacement parts on hand or to change out worn parts except for wipes; the hard rubber disks used in some designs. There are letters from the ATF on the Subguns website that address some of these problems and the ATF also has a silencer FAQ.

This is a 510 whisper silencer for a TC Encore. It telescopes over the barrel about six inches. This makes for a very sturdy mount and aligns with the bore very well as long as the barrel is a good straight one. The middle drawing shows it set up for an Enfield in 45 acp. The lower drawing is how I would have made it from steel if I was only using jacketed bullets and had more experience with silencer design.

Here is a drawing for an ar-15 silencer. I did not want to telescope the can over the barrel and I thought that the ½-28 threads for the flash suppressor were rather small for mounting a can. I machined a muzzle brake to fit back over the barrel for a snug fit and stay aligned well to the bore. The silencer attaches to the brake at two points and is held in place by 13/16-20 threads.

Here is a drawing with simple instructions on how to make a baffle. There is a tutorial on the Silencer Talk forum with photos showing the steps for making a baffle on the lathe.

If anyone has ideas for silencers, I would like to see them. I learned to operate a metal lathe while making my first silencer for a 300 whisper and am always ready to learn more. Thanks.

Ranb

 

[JRose]

Re: Silencer design

Wish I owned a lathe....

 

[dave338]

Re: Silencer design

have you got any more designs, in the uk i am allowed to make them no prob
cheers

 

[Switchblade]

Re: Silencer design

How well does the design work with the conical baffles? How reliable is it? Does it affect accuracy? Does it have a deteriorating lifespan? Just a few questions

Can it be made to simply snap in place or lock over the AR's FS/Muzzle Brake?

 

[Ranb]

Re: Silencer design

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JRose</div><div class="ubbcode-body">Wish I owned a lathe.... </div></div>
There is at least one person who is making silencers without a lathe posting on the Silencer Talk forum. I do not remember how he did it, but the end result was certainly acceptable to most who read the forum.

Even if you do not own a lathe, if you have access to one, you can make a good silencer. After getting your form 1 approved, you can use any lathe you have access to and even let someone else make the parts while you watch. You need to be present while the parts are being made and take them home with you at the end of the day unless the person helping you is an FFL/SOT class 2. Keeping a copy of the ATF form 1 with you is a good idea in my opinion.

Ranb

 

[Ranb]

Re: Silencer design

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Switchblade</div><div class="ubbcode-body">How well does the design work with the conical baffles? How reliable is it? Does it affect accuracy? Does it have a deteriorating lifespan? Just a few questions

Can it be made to simply snap in place or lock over the AR's FS/Muzzle Brake?</div></div>

Very reliable. They do not seem to degrade accuracy at all, except if there is a baffle strike or wipes are used. I have had baffles strikes, but they were caused by my 22 and 9mm silencers loosening up after shooting. Checking tightness after each mag eliminates this problem. I also had strikes with the 510 whisper can, but this was caused by improperly sized bullets that yawed 90 degrees within 25 yards. I have not had a chance to shoot my 308 and 338 target rifles at long range with the silencers attached yet. Only then will I know how the cans affect accuracy. While wipes (rubber disks) work very well at reducing sound, they ruin accuracy and wear out in less than 50 rounds.

I do not know if conical work any better than K baffles as I can not switch baffles legally without paying another $200 tax. They certainly work better than flat washer type baffles or even washers that are shaped with a ball bearing. I have read that K baffles work better with higher pressures. I like them because they align inside the can very well, better than simple cone baffles in my opinion.

Even the 22lr can erode an aluminum baffle. It is a good idea to use steel for the blast baffle instead of aluminum; it will last much longer than aluminum if you make the rest of the silencer out of it.

I only know how to make screw on attachments. There are quick disconnect ones out there. Take a look at these links for info on various manufacturers’ silencers. http://www.silencertalk.com/links.htm . for you Americans here is a list of states that allow silencers. http://www.silencertalk.com/legality.htm Kansas and Missouri recently made them legal for civilians.

Ranb

 

[11B-B4]

Re: Silencer design

The design you have looks pretty Good. 60 degree baffles are a good industry standard for sound reduction. Since you have a spacer design it would be interesting to shift the spacing around from baffle to baffle. Your baffles all have equidistant spacing, which is fine. But sometimes depending on the pressure of the round you can gain better sound reduction from spacing the baffles differently. But that round is probably fairly low pressure, so your spacing should work well. What is the diameter of the bore aperture? Also Are you going to have the aluminum parts Anodized? I would recommend it so that the threads dont gall over time. I would also make at least the muzzle adaptor and the first baffle out of either stainless steel or chrome molly so that they last longer without eroding. The blast baffle takes the brunt of the abuse from gas expansion.Looks nice though. It would be nice to hear it. Do you have an overall pic of the entire rifle?

 

[Ranb]

Re: Silencer design

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: dave338</div><div class="ubbcode-body">have you got any more designs, in the uk i am allowed to make them no prob
cheers </div></div>

Here you go. Most of these are just drawings that pop into my head and I put on "paper" using MS Paint. I have not built most of them and the design normally changes as I make them on the lathe. As they are strictly "one off" cans and will never be sold, they are fine for me. I just start with good quality straight aluminum or 4130 tubing. The baffles are machined to five thousands less than the ID of the tubing.

Ranb

 

[PLeighton]

Re: Silencer design

Is the 20 gauge can just a concept or have you built one?
Curious about such an animal.

 

[11B-B4]

Re: Silencer design

I didnt even notice the dimensions you were using... a 2" diameter and 18" overall length... The sheer volume alone of that can will swallow the sound whole

I love huge cans.

We dont make them anymore because the industry all wants the smallest can possible with the best performance so all R&D goes into making crazy baffle geometry and very scientific arrangments and configurations of baffling to try to get the most sound reduction with the smallest volume. I hate it honestly, but thats what people want. If it was up to me the cans would be 30-40% larger and be deathly quiet.

Some cans you just cant make any larger... The 22 cans, people want to be able to use on a pistol as well as a rifle, so you're hindered to producing a 1" od. I would like to make a dedicated rifle can though with a larger OD for great sound reduction. Ive made several prototypes of my own that have absolutely killed sound. They are amazing but im afraid they wouldn't be marketable. Good job on the can, make a video if you can it would be interesting to hear it. (I know videos dont do suppressors justice but its something)

 

[Ranb]

Re: Silencer design

The shotgun silencer is just a concept now. I currently have cans that fit on 22lr (pistols/rifles), 9mm (HP), 300 whisper (contender/ar-15), 338 whisper(bolt), 510 whisper (encore), 45 ACP Enfield, 308 Savage bolt rifle/338 RUM. Each time I learn a bit more about making them.

I made my first few cans large for the 300 and 510 whispers, I wanted to make sure they were effective. I think I could make them a bit smaller and have the same effectiveness now. My next ar-15 can will have .035" tubing walls instead of .065" and thinner baffles so I can go with a smaller can with the same volume or one the same size for better suppression.

My 9mm can covers the sight picture. I need to get taller sights so I can see over the can. The 22lr can is good enough at one inch, but works better on the rifles vs the pistols.

You are right about video not doing them justice. I can barely tell the difference myself.

http://www.youtube.com/watch?v=VqWuxuF1u3Y&feature=channel_page

I made another video of my ar-15 and 308 last week, I stood 50 feet away so that the unsuppressed fire did not overwhelm the microphone as much, but it is still a poor representation of what it is really like. Shooting under a roof makes the difference between hearing safe and not hearing safe too. I think my 458 socom ar-15 is barely hearing safe out in the open as it is.

Ranb

 

[19Scout77]

Re: Silencer design

The scary dude in No Country for Old Men has the patent on the shotgun supressor.

 

[bohem]

Re: Silencer design

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 19Scout77</div><div class="ubbcode-body">The scary dude in No Country for Old Men has the patent on the shotgun supressor. </div></div>

That movie got my dad to get a permit for building a 10ga suppressor. It's eeeeeerily quiet, you'd never suspect that a wad and handful of shot pellets would make so much damn noise.

 

[Ranb]

Re: Silencer design

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bohem</div><div class="ubbcode-body">That movie got my dad to get a permit for building a 10ga suppressor. It's eeeeeerily quiet, you'd never suspect that a wad and handful of shot pellets would make so much damn noise. </div></div>

Have a pic? How big is that thing? I bet it is huge to quiet down a 10 gauge.

Did he use a perforated tube inside to keep the shot cup closed? Did he port the barrel? Or did he just use baffles with a large bore to keep the shot cup from hanging up on them?

Ranb

 

[Ranb]

Re: Silencer design

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 19Scout77</div><div class="ubbcode-body">The scary dude in No Country for Old Men has the patent on the shotgun supressor. </div></div>

I have not seen the movie yet. But the silencer I have seen in stills from the movie looks like a movie prop. It seems to be way too small to be very effective, the silencer bore also looks rather narrow too.

Ranb

 

[Ranb]

Re: Silencer design

Here is a video showing an AR-15 and a Savage 308 suppressed and unsuppressed.

I shot the video 30-50 feet behind the shooters to minimize the impact of the unsuppressed fire on the cheap camcorder microphone. Both guns were significantly louder when shot under weather protection.

While the video shows that the suppressed fire is less noisy, listening to the firearms in person demonstrates a much more dramatic difference in the noise level. The subsonic 70 grain loads in the AR-15 sound the same on the video, but with much less action noise, the subsonic loads sounded much quieter to the shooter.

Ranb

 

[bohem]

Re: Silencer design

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Ranb</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bohem</div><div class="ubbcode-body">That movie got my dad to get a permit for building a 10ga suppressor. It's eeeeeerily quiet, you'd never suspect that a wad and handful of shot pellets would make so much damn noise. </div></div>

Have a pic? How big is that thing? I bet it is huge to quiet down a 10 gauge.

Did he use a perforated tube inside to keep the shot cup closed? Did he port the barrel? Or did he just use baffles with a large bore to keep the shot cup from hanging up on them?

Ranb </div></div>

He makes a practice not to post pictures of his suppressor designs online, one in particular he's working on for centerfire cans is probably patentable. That one I won't discuss.

The 10 ga can uses a perf'd tube and standard conical baffles. It's 2.5" OD stainless and 20" long IIRC.

 

[bohem]

Re: Silencer design

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Ranb</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 19Scout77</div><div class="ubbcode-body">The scary dude in No Country for Old Men has the patent on the shotgun supressor. </div></div>

I have not seen the movie yet. But the silencer I have seen in stills from the movie looks like a movie prop. It seems to be way too small to be very effective, the silencer bore also looks rather narrow too.

Ranb </div></div>

Yep, and it makes a "sproiinnnngg" noise each time he shoots it, kinda like if you flash fill a scuba tank or let a garage door spring go. It's def. a movie prop.

 

[Ranb]

Re: Silencer design

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bohem</div><div class="ubbcode-body">He makes a practice not to post pictures of his suppressor designs online, one in particular he's working on for centerfire cans is probably patentable. That one I won't discuss.

The 10 ga can uses a perf'd tube and standard conical baffles. It's 2.5" OD stainless and 20" long IIRC. </div></div>

That's cool. I guess it is a bit like the 20 gauge drawing I have above then. Except my perforated tube is the barrel and I have straight baffles. I read somewhere that straight baffles worked just as well as conical baffles when a perforated tube was used. I really have no idea though. I might go with straight baffles as they are easier to make.

Ranb

 

[HPLLC]

Re: Silencer design

The .45 enfield barrel you may want to wrap with aluminum screen. The screen has massive surface area and lots of geometry that will help absorb heat and kill sound. It's cheap and effective- it will beat the hell out of a big empty chamber. Baffles work better when the gas is released right into them. That design may actually vent gas into the chamber while the bullet exits, and then send a wave of gas out the muzzle through an unplugged 1/2" hole where it will sound loud. Again wrapping with aluminum screen will help. It will reduce volume in that chamber so more pressure exits with the bullet. Whatever isn't vented into the screen and dissapated, will have to follow the bullet through the baffling. That's theory you'd have to test it, but I'm pretty sure it would help.

You'ld then get like a two stage gas release, some gas following the bullet and other gas exiting the holes in the barrel later. The sterling is similar and it uses brass screen I think. Aluminum is superior because it absorbs heat better, but more applicable to the bolt .45 than a subgun where it may even melt.

 

[Ranb]

Re: Silencer design

I have a piece of metal screen (think it is stainless) that I wrap around the Encore barrel when configured for the 510 whisper. I have not shown the screen roll in the drawing or photo. When I use the silencer on the Enfield, I remove the spacers and stack the baffles at the muzzle end. The Enfield barrel is the same width/threads, just a different length. I put the spacers in the back of the silencer and leave the mesh in place in the can so it goes around the Enfield barrel.

I am not able to tell the difference between using the mesh and not using it. Interesting theory though. Some day when I have $3500 laying around that I do not need for another gun, I'll have to buy a good meter and microphone.

If I were to use several ounces of water on the mesh it might help more, but I have only used the water in the front on the baffles so far when experimenting. Water in an aluminum silencer is not a great idea if you want to take it apart; it gets worse if the internals are aluminum and steel. Hammering baffles out of the can makes me cringe.

Ranb

 

[hue001t]

Re: Silencer design

tag

 

[11b30b4]

Re: Silencer design

I have dabbled a bit with my lathe from time to time, I own 2 AAC cans. Are the baffles made of aluminum as well? I would suggest that the most over looked job of the can is to cool the gasses before they exit. As aluminum does not efficiently do this, its expected that results may be good but could be much better with other alloys such as iconel 718. The graphics look great and the sample you show looks good as well. Good Job

 

[Ranb]

Re: Silencer design

For the pistol and low pressure rifle cartridges I use all aluminum, except for stainless blast baffles and end cap adaptors on a few.

I have shot my 22lr and 9mm cans beside AAC silencers. Mine were both slightly louder than AAC's. The AAC cans were sealed while mine have threaded caps. I am assuming that the AAC cans had a bit more volume and most likely better baffle designs.

Ranb

 

[dead_on]

Re: Silencer design

could you post some pictures of the actual baffles in the round, (different angles, top and bottom) i have my first suppressor on the way from AAC and i m really interested to find out how they work.

 

[11b30b4]

Re: Silencer design

Ranb, i hear you. The 9mm AAc can i have is the evo 9. it has three metals in its construction 6061-T6, 7075-T6, and 17-4PH and i am not sure which is used on the baffles. But i think the key thing in sound reduction is cooling the gasses. In any case your stuff rocks.

Dead_on, glad to hear you went with AAC, you should be happy with it. If you were ask me to post pics of the AAC baffles, sorry, the construction is welded and you can not open the can without damaging it.

 

[mastersgt]

Re: Silencer design

I will have to apply to the ATF just so I can try this out. I definitely have the equipment but never considered doing one myself. With those general outlines and the photo I don't think that the average person with a descent amount of machining knowledge would have a tough time making one..

How many of you have attempted it?

 

[N2rockets]

Re: Silencer design

How long do these take you to make? Do they work as well as production models? I would be interested in making one, but have the fear of it not being properly ligned up and putting a .308 round into a chamber at the end of my gun 3 feet from my face...

 

[11b30b4]

Re: Silencer design

Machining and threading is certainly the way to go. Some of my fist attempts were using a “D” cell mag light body and before I started with the lathe I attempted to weld two threaded half’s together. Needles to say, half the can went down range following the round. I also experimented with wire mesh wrapped inside the evacuation chamber, even tried impregnating it with ultra high temp UTV to absorb some of the heat. That ended up compacting against the end cap and blowing it off the barrel all together. So Building stuff that fits and threads into place is the way to, unless you want a good laugh. I and I am sure some of you have tried the coke bottle or potato versions as well.

BTW, this is my 51st post, so I can now buy and sell

 

[Ranb]

Re: Silencer design

Here are a few more pics.

There are aluminum baffles for my 510 whisper can. I took this picture before they were used. After about 100 rounds, they are still nearly as bright. The long 20" barrel does a good job of burning all of the magnum pistol powder before it reaches the blast baffle.

Here are some aluminum K baffles from a 9mm can. With about 200 rounds of cast ammo through it the baffles had a thick layer of powder, lead and lube residue on them. I cleaned them with a scrub pad and Ed’s Red then took the photo.

It takes me about 90 minutes to make an aluminum baffle. At least double to make the same thing from 303 stainless. I tried to make some dies to stamp baffles from stainless sheet, but the metal kept on tearing, so I decided that machining them from bar stock was the way to go.

I was curious at one time to hear what a soda bottle silencer would sound like. I tried shooting my P-22 with the can emptied of baffles, it worked very poorly. Putting in just one baffle made a very big difference in the noise level. This has led me to the conclusion that it is a waste of time trying to use a soda bottle as a silencer. It might sound ok if stuffed with mesh or kapok, but then it would not last long and would probably ruin whatever accuracy you had left after covering the sights so much.

Ranb

 

[Ranb]

Re: Silencer design

I read about a guy in New Zealand who made silencers using Maglight bodies for the tube. I was considering using a D cell Maglight tube for my 300 whisper silencer body, but I decided to go with tubing and thread both ends. The flashlight bodies are a bit heavy for most low pressure applications, but they have a decent finish and look nice.

http://www.scribd.com/doc/6455050/Silencer-From-Maglite

Ranb

 

[HCA]

Re: Silencer design

Hey Guys. I applied for my Tax Stamp a month ago. How long does it normally take to get one back?? Thanks for all of your help.

 

[Ranb]

Re: Silencer design

I sent one in on a trust on 6 June 2009. It took them a week to cash the check and is still pending since then.

Ranb

 

[flounderv2]

Re: Silencer design

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Ranb</div><div class="ubbcode-body">I sent one in on a trust on 6 June 2009. It took them a week to cash the check and is still pending since then.

Ranb </div></div>

Just because they cashed your check, doesnt mean it is pending. It can take around 6 weeks to even get entered into the system at which point it goes pending.

 

[Rotortuner]

Re: Silencer design

I am at about the 3 month mark on 2 form 1's I sent in. I still havent seen them back, I would expect 3-6 months to get your stamp these days.

CJG

 

[flounderv2]

Re: Silencer design

Forms Sent June 1
Check Cased June 3
Pending July 10