I recently built my first suppressor on a form 1 back in March 2003. I did a decent if not pretty job with the lathe and MIG welder, and am waiting for two more forms to be approved by the ATF.

I used 60 degree conical baffles separated by spacers for my 300 whisper barrel. I am considering using K baffles for the 510 whisper and 22lr cans later this year. Anyone have any suggestions? Thanks.

Ranb

What's a form 1?

Damn, I wish they were legal in CA.

Have you looked at the H&K design? They patented one through US Patents office, you can pull it up on the US patents website. What I like about the design is that it is modular. The chambers are individual and thread together. I thought this would be great if you have a 22 pistol and a 22 rifle that you want to use the same setup on, just add more baffels for the rifle.

Red

Just remember suppressors work off of volume and the baffles only slow the gases down. They operate best when the clearance between the bullet and the baffles are as small as possible AND the baffles as thin as possible so they don't cut down on volume.

You mentioned a mig welder--- I'm not sure what you'd be welding. Maybe the attaching spud to the body of the suppressor? Thread the front end and make the front end removable like the Parker Hales, Winchester and Boyd's. You can stack spacer, baffle, spacer, baffle, but use a coil spring as the last thing at the front end under the cap. The baffles will make a little bit of noise but it's worth it to have the whole works cleanable. The spring gives the baffles some "give" but not much. Use a HEAVY spring. You don't want a baffle to hang up cock-eyed.....that get's exciting.

An internal volume of two thousand times case capacity works for most calibers. Fast powder works better than slow.

SOMETIMES unburned powder can build up inside the suppressor and make you seriously wet your dress when it lights off!!

[ 11-14-2003, 03:50: Message edited by: JBelk ]

I really wished I still lived in Idaho. We can own them here in WA, but not actually use them.

I made my 300 whisper (30 cal) suppressor out of 303 stainless tubing 1.625" wide, 13" long with a .050" wall. End caps from 304 stainless barstock. The barrel was machined by SSK with a port at the muzzle and threads 6" in back of the muzzle. The two mounting points 6 inches apart make this a very sturdy arrangement. I can unscrew the can half way and it is still aligned properly for shooting.

The first baffle downstream of the muzzle is 4" long and made of stainless steel. The next 4 baffles are machined out of aluminum and are cone shaped. The last baffle is a straight baffle. I was able to machine the baffles down to about .030" thickness. The baffle center holes are 0.400". The outside bearing surfaces of the baffles are 0.25" long, so they will never get crooked on me. The spacers merely keep them a half inch apart. The spacers between the baffles are made from aluminum tubing turned down to about .020".

The end caps were pressed tightly into place then welded on. The fit of the end caps is tight enough that welding is not required, but I wanted to make sure they did not come off. I am not skilled enough to make good threads on pipe yet, so I decided to put on a small bead with the MIG welder instead. The internals fit snug, but do not have to be removed with a hammer. The axial tightness is very high, nothing moves around when I shake the can or shoot. Removing the caps is simply a matter on cutting off the welds with the lathe then tapping them off. I have already done it once.

I finished by remounting the can in the lathe and trimming down the weld bead. A trip through the sand blaster gave eveything a nice even non-reflective finish. The local trophy shop engraved the can for me.

All in all it was a piece of cake to make after I quite trying to make a die set for stamping out baffle from stainless sheet metal. Turning baffles on the lathe was time consuming, but the first baffle took 3 times as long as the last three. The suppressor sort of sounds like a car door slamming, or maybe a clunk/hiss. I do not need hearing protection when shooting subsonic ammo. It does not cause gas to blow back into my face when used on my ar15. It does change point of impact down several inches at 200 yards. I also have to be careful to keep the threads clean so that they do not gall when installing ro removing. Cleaning willl be performed by immersing in solvent, pushing a 40 cal brush through, then blowing dry with air. I never plan on taking it apart again unless it is damaged.

Scrollcutter; ATF forms 1 through 5 are used for making, registering, and transfering NFA (machineguns, SBS, SBR, AOW, silencers) weapons. It is an interesting and complicated world. See www.subguns.com and the ATF website for details.

I am making a webpage to display my plans and ideas in the hope that I can learn more from others who make their own suppressors. It will be ready at the end of the month.

Ranb

An internal volume of two thousand times case capacity works for most calibers. Fast powder works better than slow.

Are you sure about that figure? My can has a volume of about 28 cubic inches. After subtracting the volume taken up by the internals, I estimate ( I made a spreadsheet to figure it all out) the can has 19 cubic inches left inside. If the 300 whisper case is .14 cubic inch volume, then this works out to about 136 times the case volume. At 13", my suppressor is not small.

You make your own suppressors? Care to share ideas?

Ranb

A Form 1 is a BATF form for letting government know you want to purchase a Class III weapon. A silencer is considered by the government's definition to be a machine gun. The government can define a feather duster as a machine gun if some wacko in the future barges into a middle school and tickles a slew of attendees (there are no "students" in middle schools anymore, they just show up most days) to death with it. It was alot different when I went to school...

"A silencer is considered by the government's definition to be a machine gun."

You are way off base here. Silencers are part of a group of firearms called NFA weapons. The National Firearms Act of 1934 regulates Machineguns, Short Barreled Rifles (SBR), Short Barreled Shotguns (SBS), Silencers, and Any Other Weapons (ex 12 gauge pistol, pen guns). Since 1986, new machine guns have not been allowed to be added to the NFA registry (except for government use). Other NFA weapons are allowed to made now. This why machineguns are so expensive, demand far outstrips supply. Persons also do not have to obtain ATF permission to move a silencer to another state. AOW's have a $5 transfer tax, the others have a $200 tax.

Ranb

Here are a few drawings I made. My 300 whisper can looks like the one in the drawing. Ideas? Thanks.

http://www.geocities.com/kaiya_bird/plans.htm

Ranb

OK, ranb...
I last looked into owning a Class III in 1984. A friend had a MAC-10 with a supressor. He had the two tax stamps; he told me BOTH gun and silencer were considered to be MGs by the government. Apparently things have changed since then. So can I license a short-barrel AR now? If I can, would it always be an SBR like an MG is always an MG once converted like you could in the good, old days?

I wish I had licensed my old Colt SP-1 in those days but the $200 was quite a bit of money for me back then. It ain't pocket change now, but I don't even blink when I write a check for that much or more for something that really needs to be paid like my recent medical bills. It's good not to be married with children...

[ 11-16-2003, 16:50: Message edited by: rootbeer ]

There is no license required for transferring a MG or SBR, just the proper form and tax stamp. You should be able to get any rifle registered as an SBR. Just bring it to a dealer of NFA weapons. He will engrave it and add it to the NFA registry usually for a small price. However, before you can take it back, a form 4 is filled out, signed by your local sherrif, then sent in with pics, prints, and $200. It is sent back to you 1-6 months later approved. I think an SBR can be removed from the registary later on.

Ranb

You may want to look into the Reflex suppressor design. Very simple and efficient.

http://guns.connect.fi/rs/Reflex.html

[ 11-16-2003, 20:43: Message edited by: Nitroman ]

I have taken many a look at the reflex webpage. I envy the Fins. Can go into a store and get a suppressor as simple as buying ammo.

Ranb

ranb...
So I take my lower receiver to an NFA dealer (we have one in Front Royal, VA), do the paperwork stuff and I leave it with him until approval? I want to go back to NV; what do I have to do about that? MGs and the like are legal there. Are there hassles with transporting an SBR across state lines, specifically the state lines of Illinois, where nobody is allowed to own a gun (except the criminals)? Can I buy a late-model lower and then build it up after getting it approved?

It would sure be nice to just walk into a gun store and buy a suppressor. Imagine, you could shoot to your heart's content and nobody would have grounds to bitch about the noise. It's my experience that shooting ranges always close at sundown because the noise would upset the dinner hour and prime-time TV viewing of the neighbors. Easy access to suppressors would obviate the problem. Hey... if people can play golf under lights, we can shoot under 'em.

[ 11-17-2003, 00:23: Message edited by: rootbeer ]

http://www.grizzlyfirearms.com/ClassIIIStates.html Look here for a summary on NFA laws. Be sure to check local laws yourself before investing any money. I know to bring a MG across state lines, a form has to be filled out then sent to the ATF. Not sure if it is the same for an SBR and SBS. You can bring a lower or frame to a dealer in NFA arms and he will registar and engrave it. Then after the ATF sends back the form 4 to you, you pick it up and put any kind of barrel on it you want.

Ranb

has anyone ever considered using a muzzle brake encompassed in a inside a silencer instead of using baffles?

Griff

Griff,

From the way I understand the suppressor to work a muzzle break inside a tupe wouldn't work very well. I think usually the muzzle break is too small to start with. And then you have the gas just directed away from the bore, it would go into the void of the tube you surrounded it with, I think that the baffels are necessary to break down the sound waves.

Of course this is all off of what I have read, since here in Kalifornia we can't play with them. :-(

Red

What is a viable source for baffles? Or must these be made by hand?

Hello:
I had a friend many years ago who built a supressor for a Mac 10. He used automotive frost plugs for baffles. If I remember rightly, he centered them on the lathe and then precision drilled the bullet passage.
Grizz

Grizz,
I, too, noticed that freeze plugs would make good baffles: they are all the same size and make their own spacing when you stack 'em. I am wondering if they are of sufficient tolerance to actually be used in a suppressor, not being precision-machined for location of center and outside diameter.

"this will come in handy for the piece of s**t city of anchorage employee that blocked my driveway with a huge snow berm"

I'm sure this was meant in jest, but with people like you in the USA, we do not need HCI helping themselves to our gun rights.

Ranb