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Discussion Starter #1
I finally did some reading to see the in and outs of how the barrel installs and have a question. From the way it apprears to me, the thread adapter on the the front of the barrel actually holds the barrel in place. Is that correct?
I thought the barrel screwed onto the upper at the rear and the adapter was just something used to add a flash hider or whatever. Does it hold the barrel in the receiver? I am wanting to make a setup that has a permenently attached suppressor. If the thread adapter is required to hold the barrel in place, then I have to put the suppressor on it and it will be removable. Alabama doesn't allow SBR from what I'm told so I have to figure a way to make the suppressor fixed on the 10.3 barrel to keep it legal.
 

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The adapter does hold the barrel in place on a short barrel. I am having the same issue since I live in Alabama. The option I have come up with, and that a Class 3 dealer told me would be acceptable is to permanently mount the suppressor to the adapter, then the adapter needs to be torqued to specs. This would prevent it from being easily changed to a SBR according to him. I still plan on calling the ATF tech branch to check with them also, I don't want to do something illegal. Also, something to consider is the overall length of the rifle, it must be at least 26" overall. The option I am going to use is the buttstock extension, that extends the rifle by 2 1/2". Hope this helps, if I come up with more info, I'll let you know. :?
 

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Discussion Starter #3
Please do. Most suppressors are at least 6" so it should be the same lenght. I am planning on soldering the the thread adapter to the suppressor which would take care of that part being removable. I was also told the same that if the suppressor was removed the weapon couldn't be fired so it is acceptable if the thread adapter was installed to the correct torque. Only thing that dosen't sit well with me on that is it still can taken off fairly easily and a flash hiders are easy to aquire. That being said it, I don't get a warm fuzzy. Does the threads from the shortened barral extend past the stock. I was thinking of pinning the thread adapter to the barrel. But there has to be enough room to access the pin with a drill bit in case it ever has to be removed for cleaning or dismantling.
 

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You do have a point about the adapter being "fairly" easy to remove, and a short flash hider could be attached, unless you JB weld or use a thread lock compound (unwise in my opinion). I believe the key would be to not have any flash hider or another adapter (with nothing permanently attached) in your possession. That is the reason I'm going to check with ATF. As for the barrel being pinned to the adapter, it won't work because the short barrel does not stick out of the receiver, it is recessed in it and the adapter screws on to the barrel inside the receiver. 8)
 

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Discussion Starter #5
Thanks for the info on the barrel being pinned to the receiver. That is what I was afarid of. On to the point of the JBweld and thread lock, while I can't account to the truth of the statement but we in the Air Force never apply these compounds to anything that requires a torque because it changes the final torque value. I just figure it makes sense when you apply a torque to something that is designed to jam up the threads. Also I am thinking about the resonance of the barrel when a substance is applied. JB Weld hardens to a brittle metal substance and Lock tight will form a hardened jel. I would think they might play a factor on the resonance of the barrel. I am just assuming but that is based on the reason of using full floating barrel on high precision rifles (Nothing changes the vibratation of the barrel as the bullet travels down it). If these substances are applied, would it affect the travel of the bullet once it left the barrel.
 

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I really would not put JB weld on my barrel and adapter, but the loctite solution is very light and almost like an oil solution when initially applied, which makes me think it would not affect the torque. As far as bullet travel, I do not think it would hinder performance either since there is a spring located inside the front of the reciever that buffers the barrel shroud on the long barrel, and buffers the adapter on the short barrel. Back to overall length of the rifle, on my measurements, you will at least have to have a suppressor that is 7 1/4" to meet the overall length requirements on the gun. Most of the suppressors I have been looking at are around 6 3/4" or less, that is why I am going with a buttstock extension. With an extenstion, you can also permanently mount a 5 1/2" long flash hider and have a legal length gun, which is what I am doing until I get my suppressor. I just hate that Alabama has such a rediculous law, I would SBR mine in a heartbeat if it were allowed. I can have my full auto registered Thompson that has a short barrel all day long, but I can't register a SBR, rediculous! :evil:
 

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Discussion Starter #7
I thought the suppressor would have been longer. What suppressors have you looked at? I have contacted a few people that say they offer them and as soon as I mention lets get started on the paperwork they never respond back. Really starting to irritate me. Read in another post here that there is a guy in Georgia that builds them company name is G-Man weaponary. Might call him this week. Think I also might start looking at AR cans. Told they are the same and will work just fine. Have you decided on who you are goingto use yet?
 

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I have been looking at the yankee hill .223 suppressors, they are cheaper, and possibly better than the ones specifically for the 5.7 round. The yankee hill suppressors are almost 7" in length, which is not quite long enough to make the gun 26" overall.
The problem is there are not a whole lot of class 3 dealers, and you need to find one that is going to stay on top of the paperwork and look out for your interest. I haven't decided on a dealer yet, but there are some guys from Athens, and another guy from Pell city that I'm looking into using. Not sure where you are in Alabama, but when I get there contact info, I'll let you know. Also, l would like to know what kind of suppressors you have looked at and how long they are, and the price range? The yankee hill that I've looked is in the $500 range.
 

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Discussion Starter #9
I looked at the gemtech 5.7, its like 450 but its for the 5.7 pistol. Said it wouldn't hold up to the pressures of the PS90. Been contacting thomas machine but I have no idea whats going on with him. Everytime I contact him about a suppressor and barrel he replies back after several days. Still working the barrels, which is cool, but I want to start the paperwork for the suppressor and he never replies back so I don't know what the deal is ( Maybe he does do that type of stuff, I wish he would let me know). I looked at one gemtech called the HALO. States its 7 3/4 in long. And goes for 695. Its a heavy duty unit made for the .223. Also have started to look at some of the Yankee hill units. Really like the Phantom. Thomas machines unit is 325 but dosent seem I will ever be able to buy it from him.
Please let me know when you have the info back from the state regarding what they consider the set up we are looking at to be. I am still active military stationed in Arizona so I really don't any contacts there to help out.

I do have one question on the measurement on the barrel. Maybe I am missing something. The shortened barrel are from 10.3 to 10.5 inches depending on the manufacturer. The thread adapter has to be used and I am guessing that would add 1/4 to 1/2 inch to the barrel. The suppressors are 6 7/8 inches. The barrel and suppressor alone have a length of over 17 inches. The stock barrel is 16.04 inches long. Once the setup is installed the gun will actually be about a inch longer then before. Am I seeing everything here? If that is correct there wouldn't be any need for the buttstock extention.
 

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I measured the rifle length from the buttstock to the threads on an attached adapter and short barrel, it is 18 5/8". This would indicate to me that the suppressor would need to be at least 7 3/8" to meet the overall length requirement on the gun. I hope this is more helpful. I will post pictures when I get time. I just had the long flash hider silver soldered to the adapter, and I like the look of it, but like I said, I had to add the stock extension to make it legal length.
 

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to be considered a permenant install im pretty sure they are going to make you drill and pin the adapter on. not a big deal really.
 

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I don't think there is a way to pin things when the barrel doesn't extend out of the receiver.

With a custom cut barrel and a custom made adapter you could pin it.

I have been reasearching suppressors recently and the gemtech M204 (the can they recommend for the ps90) has had some very poor reviews. I wouldn't recommend it.

I have settled on an ACC can, but it won't be dedicated to the PS90.

Good luck with your projects! And let us know what the ATF has to say.
 

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Discussion Starter #16
Think i'm going to try out a Yankee can. Friend has a few different vendors cans so I get to play. :twisted:
 

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Streetrod,
Another option you might want to consider is one I've seen my class 3 dealer do to his ps90. He just cut the standard barrel shorter, cut the barrel shroud shorter to where it is about 1/4 to 1/2 inches shorter than the barrel when you have the shroud tight to the receiver. I'm not sure of the thread size, but he rethreaded his barrel to attach to his suppressor. He screwed it down so the suppressor is tight against the shroud and the shroud is tight to the receiver. From that point you can silver solder or weld the suppressor to the shroud, and since the barrel is longer, it would be easier to blind pin the shroud to the barrel. Just another option to consider.
 

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Discussion Starter #18
Well guys the barrel is being made. I just talked with Brett at Hi-Desertdog and he is kick ass. He went thru all the issues of the SBR problem and the issue of the length. End result is he is going to custom cut a barrel and make a extended thread adapter to match the length with the suppressor measurement I gave him to meet the 16" barrel rule and the 28" weapon length rule. That is so cool. I also asked about pinning the thread adapter to the barrel because of the Alabama law that I will have to abide by. He is going to drill the thread adapter to accomdate a blind pin. Total deal is about 240-250 and I don't supply a barrel. Man, I can't be happier. Well, If i got it tomorrow I guess I could be but I don't mind the wait. He is great to deal with. Can't wait to get it. :?
 

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Supessors and the P90/PS90

Hello all, new to "this" site. I have seen alot of questions on the Gem Tech cans. My personal opinion is you can do much better than Gem Tec. YHM, AAC, AWC and many others do much better. You should also look into Quick Silver cans. If you're not doing full auto you can also use a 22LR can that is rated for full auto. This will handle the pressured of the 5.7 just fine without the expense of a can rated for 5.56.
 

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Re: Supessors and the P90/PS90

Drkhorse8541 said:
Hello all, new to "this" site. I have seen alot of questions on the Gem Tech cans. My personal opinion is you can do much better than Gem Tec. YHM, AAC, AWC and many others do much better. You should also look into Quick Silver cans. If you're not doing full auto you can also use a 22LR can that is rated for full auto. This will handle the pressured of the 5.7 just fine without the expense of a can rated for 5.56.
I think we've all pretty much figured out the can thing for the PS90, but thanks for bringing a thread back from the dead. :D
 
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