Suppressed FAL

[shlomo]

...if ya don't line-bore yer silencer, it'll sound "off"... everybody knows that except Dubya and GP...hehe...vent yer bleed hole into the can with some rubber hose, like a water-cooled sheen gun... hehe...

[Tyris]

Originally posted by ggiilliiee
bet yer action makes more noise than the vent hole ...

The noises are different. I experienced this when my local 07/02 dealer and I silenced my 5.45 AK. The loudest noise by far was the gas venting from the 4 holes on the AK gas block. Action noise was not nearly enough to ring my ears, but the venting gas was.

We ended up welding the gas vent holes and beefed up the recoil spring with a Wolff +15%. The gun still functioned fine with and without the silencer.

-T

[shlomo]

Originally posted by Tyris


No, that was fine, I follow you.

How about this: What happens if we incorporate the screw mechanism into the notchless gas-plug itself? Basically add an adjustable screw into the front of the gas plug. This avoids the necessity of drilling the gas-block, and retains the ability to adjust the gas on the FAL, just in a different manner than using the collar.

sound plausible and relatively painless with no major mods to the rifle?

-T

That's pretty much what I was saying. Hollow setscrew in the custom notchless plug. Only diff was that I was thinking installing the screw and stopscrew from the rear, as opposed to the front--which is what I think you're describing. The front actually makes more sense in a certain way, since the screw(s) wouldn't have to be hollow.

Lemme think on this a while.

[gunplumber]

I've been thinking about a 5.45 can just for kicks. Just trying to decide between a PBS-5 style for looks or a PBS-1 for convenience. What are you using on your 5.45?

[Tyris]

Originally posted by gunplumber
I've been thinking about a 5.45 can just for kicks. Just trying to decide between a PBS-5 style for looks or a PBS-1 for convenience.

I used a 223 can for availability. It does triple duty on my AUG, rem700 and 545 AK

-T

[Tyris]

Originally posted by shlomo


That's pretty much what I was saying. Hollow setscrew in the custom notchless plug. Only diff was that I was thinking installing the screw and stopscrew from the rear, as opposed to the front--which is what I think you're describing. The front actually makes more sense in a certain way, since the screw(s) wouldn't have to be hollow.

Lemme think on this a while.

I think we're on the same page now. I think I misread the part about threading the main gas-hole in your post.

The reason I favor the front for the screw is it will allow some degree of field adjustment, even if it requires a small screw driver or some tool.

-T

[gunplumber]

The only thing making the front inaccessible is the spring loaded plunger. The only reason for the spring loaded plunger is to index the plug. So with a different method of indexing the plug, the cylinder is free for modification. At that point, almost easier to make a new one from scratch.

I am looking for a better picture, but since POFs use a FAL type piston (Frank prototyped them in my shop from StG components) they are worth looking at. Here the end of the piston is reversible. Need a better pic, but IIRC it was a tappet system like the SKS/G36/tokarov '38

[shlomo]

Originally posted by Tyris


I think we're on the same page now. I think I misread the part about threading the main gas-hole in your post.

The reason I favor the front for the screw is it will allow some degree of field adjustment, even if it requires a small screw driver or some tool.

-T

Well, the chief obstacle to the front adjustment is the springloaded retainer button, which has a shaft that crosses thru the front of the plug right in front of the area we're talking about. That's what I'm pondering right now-- how to lock it in the block.

ETA--looks like GP and I crossposted the same thing.

I'm actually working on a scratch made plug right now.

[gunplumber]

there was once an adjustable galil gas piston - two piece threaded. Supposedly the OAL length of the piston would control the amount of gas pressure. Not sure how well it worked. Problems with 2 piece pistons on the FAL are pretty well documented. Although maybe it was shoddy workmanship not the principle.

[Dopavash]

Originally posted by shlomo


Well, the chief obstacle to the front adjustment is the springloaded retainer button, which has a shaft that crosses thru the front of the plug right in front of the area we're talking about. That's what I'm pondering right now-- how to lock it in the block.

ETA--looks like GP and I crossposted the same thing.

I'm actually working on a scratch made plug right now.

An oval cut in the shaft of the button would allow a sleeve/screwshaft to be mounted in it and retain the motion of the button. I bet it still conflicts with the spring, however.

[shlomo]

Well, here's the plug blank, sans vent holes and lock button. Already tried it in the Imblel block, and it fits like the original. Soon as we figure out which way to jump with the vent system, I'll get on it.

[stimpsonjcat]

How did I miss this thread?

I have made several of these now. I grind out the area around the hole in the plug, weld it over, anneal, and then redrill with a smaller bit. I also weld up the notch that normally allows gas to escape at the collar.

The gas piston idea will work, but the problem is the high-pressure gas coming out the bleed hole makes NOISE. So the best solution IMHO is to limit the gas getting into the gas system and try to use it all to move the piston.

The new hole I settled on was about half the size of the original...somewhere around 0.06" IIRC.

My FAL functions fine with my home brewed can with this plug, but even so I think it is borderline hearing safe. It is still noticeably quieter on the grenade setting.

The ultimate solution would be a custom gas tube with no bleed holes and a custom plug with a hole only just big enough to cycle.

[shlomo]

So, Stimp,

Are you saying that even with the notch welded shut and the gas ring closed down, you still get gas out of the regulator? Enough to be a noise problem?

[stimpsonjcat]

Oh Shlomo the plug is niiiiice!

I like the idea of the front adjust gas plug!

I'll spend some clock cycles on the retention method also.

[stimpsonjcat]

Maybe, not sure where it escapes, my bet is at the gas tube holes, as I thought it was fairly quiet and the guy to my right thought it was loud.

So I probably need to try a smaller plug hole with a holeless tube.

I think this is like standing to the right of a suppressed AR, you get high pressure gas out of the bolt holes and it is louder there.

Oh hey, I wonder if I could make a tube with an xternal sleeve that could close over the holes in suppressor mode? Take an existing tube, add 2 notches, then make a sleeve that has a part outside the handguard joint for adjustment.

I'll F with this after I get the Bren refinished.

[stimpsonjcat]

[stimpsonjcat]

I thought up a solution for the gas plug I think would work.



Essentially we make a piece that is cyndrilical, fits inside the existing cylinder in the gas plug, has a smaller diameter shaft that extends thru the front of the plug that allows it to be rotated to one of two positions for minimal or standard gas.

Of course this omits the hard part of making the inner device stay put and the plug itself stay put, but it solves the gas selection criteria externally and follows the WECSOG rules of modifying the cheap part.

[shlomo]

Way more complicated than what I had in mind, Stimp, but along the same line.

I had just thought of boring the hole all the way thru, and tapping the front part. Then make and install a sort of rod that is unthreaded on the back end, and has a section of threads on the front end. Kinda like a 1" hex pocket setscrew with the threads turned off the rear part, leaving a cylinder to match the bore of the plug where the gas port is. It could be turned in and out of the plug with an allen wrench, to partially occlude the gas port.

[tac-40]

Why try to make a dual purpose plug. You have to install and seat the supressor and that is not very fast if it is threaded on, faster if you are using a QD brake/hider. Just make a dedicated plug for use with the supressor. Add one of the DSA levers actuators for a tactile indicator of which way it needs to go.

stimpy's idea of an outer sleeve on the gas tube is great and it can be vented towards the rear to keep the gas from blowing in your face. Moving it can be simple. Weld a small handle to it perpendicular to the axis. Cut a corresponding slot in the hand guards with notches on either end. Rotate the hand up into the slot and slide the sleeve forward or back and then rotate the handle in to the other notch to lock it into place.

[brunop]

If there is a cooler place on the entire internet, I've never heard of it.

Y'all kick ass, and I love this place.

Peace.

[shlomo]

Originally posted by tac-40
Why try to make a dual purpose plug. You have to install and seat the supressor and that is not very fast if it is threaded on, faster if you are using a QD brake/hider. Just make a dedicated plug for use with the supressor. Add one of the DSA levers actuators for a tactile indicator of which way it needs to go.

stimpy's idea of an outer sleeve on the gas tube is great and it can be vented towards the rear to keep the gas from blowing in your face. Moving it can be simple. Weld a small handle to it perpendicular to the axis. Cut a corresponding slot in the hand guards with notches on either end. Rotate the hand up into the slot and slide the sleeve forward or back and then rotate the handle in to the other notch to lock it into place.

Tac,

Mine ain't dual purpose. It's just for this app. Hence, the scratch-built plug above with no notch. We're just hashing out the details of the (necessary, IMO) gas adjustment design.

Stimp,

Seems like a good way to test whether the noise is coming from the piston tube vent holes is to wrap a beer coozie around the grill area and see what, if any, diff it makes in the sound volume.

Brunop,

I don't know why they even let a guy like me hang around.

[shlomo]

I think I have an idea for the retainer button. Gonna do some dimension checking this evening to see if it's workable.

I do all my best thinkin' on the Throne.

[stimpsonjcat]

Well *I* already have a 'simple' solution...was just trying to make life easier for those following along.

As to the sleeve, it'll be even easier for me as my modified HB handguards already have a lovely opening on the top letting me access the gas tube.

Just had another thought. Same design I had above, but with the half-cylinder set to move IN or OUT on the plunger, then cut two hlaf cuts in the shaft where it passes the existing rod in the spring detent, then cut the rod in the spring detent to match the shaft cuts for position retention.

So to adjust normal or suppressed, depress the existing detent on plug and push or pull on the shaft to adjust the position of the half-cylinder.

[gunplumber]

sketch?

[tac-40]

stimpy, that sounds like a good idea. How is the recoil on a canned FAL? I know they say a can reduces it significantly. The reason I ask is how will you keep the pin in the proper position (min or max) under recoil since you can't spring load it like a normal plug.

[shlomo]

Hmph. Jilted.

Ya'll three kin smooch my pimply butt. I'm gonna go it alone then, and we'll see who laughs last.

[tac-40]

I had to make nice with him since he was coming to moses' match. You could have come along too. You sure missed some outstanding shooting. We didn't talk too much gun stuff except for the Bren build and his Kfal.

OBTW, if you ever shoot with Rob, don't use his sight dope. It ain't right.

[L Haney]

Originally posted by tac-40
The reason I ask is how will you keep the pin in the proper position (min or max) under recoil since you can't spring load it like a normal plug.

Tac, re-read what he said above. He's gonna' put recesses in the plunger shaft that will get captured by the existing button. That is simple and most elegant. Got some smart fellers on here. Meanwhile, Shlomo sits on the porcelain lazyboy and cogitates swarf. I think the world is revolving smoothly again.

[stimpsonjcat]

Originally posted by L Haney


Tac, re-read what he said above. He's gonna' put recesses in the plunger shaft that will get captured by the existing button. That is simple and most elegant. Got some smart fellers on here. Meanwhile, Shlomo sits on the porcelain lazyboy and cogitates swarf. I think the world is revolving smoothly again.

That is a fine piece of summation there El.

'cogitates swarf' I LOLZD...ain't that the truth.

Don't get all butt-hurt big guy, your from scratch plug has me drooling.

[shlomo]

[tac-40]

Yep, it was late and I was tired. Reread it and it is perfectly clear. My confusion stemmed from his drawing of the rotating cylinder and his description of the sliding cylinder. I was trying to combine the two in my thinking. Didn't workl.

And lay off the literary imagery of shlomo at rest. I think I popped a few brain cells when that picture came into the mental view port.

[stimpsonjcat]

Oh I finally see why Shlo was upset.

Top post this page was pointing out that the parts I already made work fine...not trying to say the new nonsense I am spouting is better than your designs.

Heck at this point I don't even have a spare plug to butcher.

[shlomo]

I warn't upset. Hence the winky-face.

But you're right--I thought you were talking about the drawing you showed on the previous page. I just figgered all three of ya's were hot on that design, which did make me wonder a bit...

In any case, since that wasn't the case, ya'll kin UNsmooch my pimply butt.

I have not yet made a trip to the ironmonger for some suitable setscrews, but I have been measuring and mulling....

[lew]

Any suppressors out there that fit on the combo device? I really don't want to alter the rifle's current state. Figured I could throw a combo device on a planned bolt action as well to be able to switch between the two. Once I move out of this God-forsaken state, a couple of cans are on the list.

[Scott V2]

Yankee Machine has a can that has an adapter to fit standard FAL threads.

I have been in OH for over a year now and am considering a can. The county I am in requires the LEO to sign permits regardless of their personal feelings, unless you have a record of some sort

I want to try a suppressed FAL before I spring for a can. I have been told it helps with noise levels, but that hearing protection is still necessary. If that is the case, I will probably pass

[lew]

I welcome any sound reduction. My hearing is very resilient. Loud music doesn't bother me one bit, but a gunshot even with muffs and plugs is still slightly uncomfortable to me. Plus, I could whip up some subsonic loads to help out.

Do you know how solidly they mount, i.e. suitable for precision shooting with the bolt gun?

[LAFAL]

I have a YHM 7.62 stainless and a 5.56 coming- hopefully will go pending in a few weeks. I ordered the M1-A, FAL and standard adapters for my .308s. The FAL one is wicked- has sharp pointy teeth on the end. The M1A one has a standalone front sight base that I'm assuming you have to index to 12 Oclock and will nest against the back of the adapter. I've found some subsonic load data on the web and there are some nice Utube vids of suppressed FALs, bolt guns etc with the YHM units.

[Artful]

The Yankee Hill Machine replaces your combo flash suppressor - It should be good for precison shooting - I use my AAC Cyclone on both my FAL and my Remington 700V bolt action - mine is threaded 5/8x24 so I had adaptor made from standard FAL 9/16 to 5/8 - the main advantage of YHM is quicker thread on and off than standard 24 or 28 TPI.

As far as noise reduction it goes from standard 160+ impluse to 120+ impluse but still louder than a unsupressed 22 pistol - the smaller the cartridge the less powder the less nose and the smaller the diam of the bullet hole the less noise will be also.

Subsonic load data can be found but just be careful of powder position in the case as velocity can vary much between shooting uphill and down hill.

[LAFAL]

So your powder should fill the case or can you use a fiber filler on top of the powder? Would the unburned filler fill or clog the baffles?

[lew]

Originally posted by Artful
The Yankee Hill Machine replaces your combo flash suppressor - It should be good for precison shooting - I use my AAC Cyclone on both my FAL and my Remington 700V bolt action - mine is threaded 5/8x24 so I had adaptor made from standard FAL 9/16 to 5/8 - the main advantage of YHM is quicker thread on and off than standard 24 or 28 TPI.

As far as noise reduction it goes from standard 160+ impluse to 120+ impluse but still louder than a unsupressed 22 pistol - the smaller the cartridge the less powder the less nose and the smaller the diam of the bullet hole the less noise will be also.

Subsonic load data can be found but just be careful of powder position in the case as velocity can vary much between shooting uphill and down hill.

Well shit. I'm trying to keep the combo device in place. I hate to alter an original piece (the rifle) if I don't have to.

Got it on the subsonic loads. Any favorites you'd care to share?

What about this one: Advanced Armament 762-SD

[stimpsonjcat]

There's more to making it queit than just the can.

Here's some light reading:

http://www.falfiles.com/forums/showt...hreadid=295677

[lew]

The thought on gas venting had crossed my mind. Good to know folks with more machining experience than I are working on it.

[Artful]

Originally posted by lew


Well shit. I'm trying to keep the combo device in place. I hate to alter an original piece (the rifle) if I don't have to.

Got it on the subsonic loads. Any favorites you'd care to share?

What about this one: Advanced Armament 762-SD

Nope not that one - most 30 cans require either thread on barrel or special flash hider adaptor - there are some cans that use a standard A2 flash hider as the mount - SRT Patents-Pending Atlas Universal mount (AU2) which attaches the 223 Typhoon suppressor to any Mil-Spec A2 flash hider. Gemtech's 223 Halo is another, and Coastal Extreme Duty 5.56mm Suppressor with Flash Hider Mount.

But I don't know of any 30 cal can's doing it.

Oh an put your gas on Grenade - give you a straight pull rifle with no gas venting except thru the suppressor.

[lew]

Damn. That stinks. Think anyone would be willing to whip up a custom? As you can see, I'm really loathe to "butcher" my FAL by dickin' with the muzzle device. Might just say "screw it" and get a can solely for the bolt gun. Of course, this all based on my ability to leave this state (MI), or, by some divine stroke of intervention, us peons are allowed the fun stuff, but that's not gonna happen anytime soon.

[Artful]

Doubt Gemtech would be interested but try Doug at SRT, he does custom stuff pretty regularly - I'd check out his thoughts and get his 30 cal Shadow XL Titanium and see if he would make up something that would work for ya. Then of course you need to put a Combo flash hider on your bolt gun.

I wouldn't give up on being suppressed, here's mine
http://www.youtube.com/watch?v=wMIomwkvyBQ

as for reloading subsonic 308 try this tread
http://www.quarterbore.net/forums/showthread.php?t=280

another comparison from someone else
http://www.youtube.com/watch?v=27xXvaZYjmA

remember the video's you watch do not capture all the sound
so be aware reality doesn't match what you hear thru your speakers.

[lew]

Originally posted by Artful
Then of course you need to put a Combo flash hider on your bolt gun.

Oh no. Please don't make me do that.

I like somethin' hangin' off the end. Naked muzzles look weird The combo device looks the best, IMO. Probably have iron sights on it, in addition to the scope, simply cuz I like my irons. I may as well have fun with the project.

I'll be sure to give the lad at SRT a holler.

Between the suppressor, subsonic loads, and a modified gas plug (following Stimp, et al's thread there), it's off to the races. Should be a fairly quiet beast when all is said and done. Not Hollywood type, but enough so anyone outside the immediate vicinity won't raise an eyebrow.

Thanks to the lot o' ya. Now I have somewhere to start from.

[Artful]

Originally posted by lew


Oh no. Please don't make me do that.

I like somethin' hangin' off the end. Naked muzzles look weird The combo device looks the best, IMO. Probably have iron sights on it, in addition to the scope, simply cuz I like my irons. I may as well have fun with the project.

Yep it does look different but you have to love our little custom excursions.




I thougt of another custom suppressor maker David Saylor at Liberty Suppressors.

[lew]

What caliber's the Winchester (?)? As for the M38, why would you want to cover up most of the fireball?! And what muzzle device is that on the FAL?

[Artful]

The Mauser is 7.62x39 using WASR mags, the flashhider is turned in (built into) the barrel not an add on.

M38 scout is just for fun. As I get older I like quiet more.

The FAL and the M38 are both showing AAC Cyclone Can mounted (same can you just moved between guns)

[lew]

Neat sticks. I like the Mauser. Well, I kinda like 'em all. What year's the M38?