FN Herstal Firearms banner

1 - 19 of 19 Posts

·
Registered
Joined
·
12 Posts
Discussion Starter #1
Don't know if this should go into 'accessories' or not, but here goes.

I am looking into an SBR PS90 from CMMG. I pretty much don't buy firearms anymore unless I can attach a silencer, so I asked CMMG about getting the SBR set up for a silencer. Their only answer is that they reccomend the Gemtech bilock, but no other adapter for silencer use.

I have several silencers that would work fine on the SBR PS90, but none will interface with the Gemtech Bilock. I really don't care to buy a new dedicated silencer just for the PS90. My only other Gemtech silencer is a Mossad for the Uzi. It is an ok can, but it is somehow the largest and loudest 9mm can that I own, out of 6, so I don't think I will buy another Gemtech. Plus, I have heard that some users have had negative experiences with the bilock, namely gas escape around the can-mount interface that blows towards the sights.

Has anyone put a silencer on an SBR PS90? What was your can and mounting solution?

TIA
 

·
Registered
Joined
·
21 Posts
I got an SBR PS90 from Mark at www.trosusa.com. He threaded the barrel with the standard AR-15 threads, then installed the AR birdcage flashhider. Works great with any suppressor that uses the 1/2x28 threads.
 

·
Registered
Joined
·
142 Posts
DanceTiger said:
I got an SBR PS90 from Mark at www.trosusa.com. He threaded the barrel with the standard AR-15 threads, then installed the AR birdcage flashhider. Works great with any suppressor that uses the 1/2x28 threads.
Didn't you use the adapter that allows you to use AR15 muzzle attachments? You need something to hold the barrel itself in place.
 

·
Registered
Joined
·
121 Posts
I havent seen FN sell directly to civis but its worth asking them about this.


The other option is to get a .223 can and use it on the PS90. You can get the most bang for the buck this way. You also have a ton of mount options and manufacturers too.

In this shot you can see a .223 mount on a P90. This is the AAC M4-1000 mount I believe.

 

·
Registered
Joined
·
12 Posts
Discussion Starter #5
Thanks for the help so far.

The FN can would definitely be unavailable to civilians, as it is imported. Not a big deal, though, since the best silencers in the world are made in the USA. This is almost certainly attributable to civilian demand and the ease with which manufacturers can make and sell silencers.

CMMG is pretty adamant about only supporting the gemtech bilock and recomends against using a thread adapter. I am mystified by this since there is no difference from an engineering standpoint between an adapter that has a special lockup and one that has 1/2X28 threads. Actually, there is less potential for tolerance screw ups in an adapter with threads vs a special spring loaded lockup.

I think I am just going to get a CMMG SBR and add a TROS 1/2X28 adapter. I can use my .223 can for full power ammo or 9mm SMG can when shooting subsonics. Mark Mcwillis from TROS uses his adapter on TROS's SBR conversions and even says it is compatible with CMMG's barrels. The purpose of the TROS adapter is to provide compatability with .223 silencers normally used on the M16/AR15.

Maybe there's a commercial reason for CMMG supporting the bilock only?
 

·
Registered
Joined
·
121 Posts
Nah I just think that Gemtech was the first on the 5.7 platform so they are the ones that come reccomended. I have heard logs of bad things about the bi lock mount the more I read about it. I was pumped up to get one for the PS90 earlier this year until I read about the srping failures and blow back issues. Although the blow back issues arent as bad (for optics) on a P90 because the barrel is vertically below the optic. The other thing that is nice about the gemtech Fh is that it uses the factory FN threads. Where if you put a 1/2 28 pitch on your barrel you can't have the FN FH on it ... which makes me sad.

If you don't mind a screw on can that thats actually what I would suggest. Why even get the tri lug for subsonics? Just use the .223 can if you already have it. Its gonna have more DB reduction than the 9 tri lug can anyway. To me a QD option, just some of the time wouldn't be worth chancing shooting the wrong ammo through your trilug can and blowing it 50 yards down range. Stick with the .223 can if possible. Its rated to take the abuse.


Well FN has a plant here so I wasn't sure if they were making cans here as well. Its worth asking em, but I'm sure we would have heard about it.

Hell, I ordered a barrel to thread for my steyr and its going to take 2 months because they close the plant in austria in the begining of august for some holiday. Most companies that have plants here still make almost everything they can over seas.

Anyway good luck in your project. Post some pics after you get it all figured out.
 

·
Registered
Joined
·
120 Posts
Just use the CMMG barrel with their .5x28 thread adaptor that goes on in place of the standard or Gemtech Bilock FH. Mount your A2 style FH and Bob's your uncle.
That's the route I'm going. I'll be using the AAC M4-1000. With the suppressor unmounted it'll look like the P90 in the pic above. With the suppressor mounted it'll add an additional 4.75".
 

·
Registered
Joined
·
12 Posts
Discussion Starter #10
Abiqua14 said:
Just use the CMMG barrel with their .5x28 thread adaptor that goes on in place of the standard or Gemtech Bilock FH. Mount your A2 style FH and Bob's your uncle.
That's the route I'm going. I'll be using the AAC M4-1000. With the suppressor unmounted it'll look like the P90 in the pic above. With the suppressor mounted it'll add an additional 4.75".
I just wish I knew for sure the 1/2X28 would work for silencer use. If it were that easy, why the warning about the CMMG thread adapter not being for use with a silencer?

Is the flash hider non-removeable on a P90 (or hard to remove)?

TIA
 

·
Registered
Joined
·
120 Posts
Here's what CMMG's website says about the .5x28 FH/adaptor:


"P90/PS90 SBR 1/2x28 Thread Adapter

New production 1/2x28 thread adapter for P90/PS90 SBR. Replaces standard flash hider and allows mounting of most AR hiders/suppressors."

I think that the "not for use with suppressors" bit is for the FH's listed just above the warning.

The FH on a PS90 is what holds the barrel in the receiver. The FH acts as a barrel nut holding the barrel under tension. Very similar to a Walther P22, if you've ever taken one of those apart. I've replaced the standard barrel nut on my P22 with a .5x28 threaded version, just like what I'm gonna do with my soon to be SBRed PS90.

Really, both the .5x28 and the Bi-lock do the same thing, act as a barrel nut and offer conversion to a standard connection on the other side.
 

·
Banned
Joined
·
58 Posts



Anyone tried this?

While I realize it looks disturbingly like a toilet plunger, I'd rather not touch the barrel if it all possible, but if I can get a flash suppressor that isn't 'faux' then that's what I would prefer.

Anyone have any experience with this?
 

·
Registered
Joined
·
12 Posts
Discussion Starter #13
Abiqua14 said:
Here's what CMMG's website says about the .5x28 FH/adaptor:


"P90/PS90 SBR 1/2x28 Thread Adapter

New production 1/2x28 thread adapter for P90/PS90 SBR. Replaces standard flash hider and allows mounting of most AR hiders/suppressors."

I think that the "not for use with suppressors" bit is for the FH's listed just above the warning.

The FH on a PS90 is what holds the barrel in the receiver. The FH acts as a barrel nut holding the barrel under tension. Very similar to a Walther P22, if you've ever taken one of those apart. I've replaced the standard barrel nut on my P22 with a .5x28 threaded version, just like what I'm gonna do with my soon to be SBRed PS90.

Really, both the .5x28 and the Bi-lock do the same thing, act as a barrel nut and offer conversion to a standard connection on the other side.
Abiqua-

Thanks, this clears up alot for me. If it's that easy to swap then I can get an FN P90 FH and then a TROS 1/2X28 adapter and have a good no comprimise solution. I was afraid I'd be locked into whatever came installed from CMMG.

CMMG actually told me that they don't reccommend any other attachment method for silencers besides the Gemtech bilock, and that their adapter "isn't reccomended for silencers." I asked 2 different people just to make sure. I guess they don't make them to tolerances they are comfortable with, unlike TROS or Gemtech.
 

·
Registered
Joined
·
121 Posts
Is there any reason you have decided not to got the fast attach route? I realize the AAC mount in that picture doesn't look as nice or as short as the FN FH but it really solves all the problems you are trying to.

Do you have an existing threaded .223 can you are trying to use? If so you should probably call up the manufacture and see if they have done testing on the p90 using it.
 

·
Registered
Joined
·
12 Posts
Discussion Starter #15
It's a threaded .223 can. I didn't want to have to get a new silencer just for the PS90.

I hadn't thought there would be a problem with a .223 can with the 5.7 round. Does it not use the same .224 diameter bullets as the 5.56, just with a much smaller powder charge?

Incidently, the 1st P90 I ever saw was at Knob Creek. They actually attached an AAC 9mm can (the quick attach beretta model with sights) and rocked the gun all day as a full auto rental with cases of SS192. The can worked fine all day, so I figured any .223 can should easily be able to handle the P90 series guns.

Are there issues I'm missing with the P90/PS90 and silencers?
 

·
Registered
Joined
·
121 Posts
I think a .223 can would be perfectly fine on your PS90. I can't imagine a 9mm can holding up on FA use. The presure of the 5.7 round should have killed it. That is almost too hard to believe.

Anyways the only thing that you need to worry about with the PS90 is the barrel. Its not the same as putting a can on an M4 or MP5 because of the way the barrel is designed. So the best bet is to call the can munufacturer and ask them about using it on a PS90. You may get thier blessing on it in 5 minutes and you can stop wondering if it may or may not work.

Which can is it?
 

·
Registered
Joined
·
120 Posts
As an FYI, AAC recommends their M4-1000 for the PS90. Their FIVESEVEN suppressor is designed only for the 57 pistol.
I know that they make FH's that fast attach mount the M4-1k for a variety of rifles (including a generic .5x28) but I don't know if they make a PS90 specific FH so you don't have to use an adaptor. They made a mini A2 style FH for a specific application (I don't remember what), that would be a nice fit for the PS90 but it's no longer in production.
 

·
Registered
Joined
·
14 Posts
Gemtech G-5 , Advance Armament M4-2000

Maybe this will help. I have two PS90 SBR’s one has the Gemtech G-5 Bilock and the other Advance Armament M4-2000. Both cans are made very well and perform very well. I have right at 2000+ subsonic rounds and 3000+ ss197SR, ss190, ss191, ss192 rounds with no problems or can cleaning yet. My personal pick is the G-5 it is shorter and 3 sec and it’s on. The grate thing about theses two can is I can put them on my AR’s. I also have the Five-Seven IOM with Gem tech’s FN-57 can with about 1000+ Subsonic rounds and 500+ ss197SR, ss190, ss191, ss192 ran through the can with no cleaning or problems. If you want it quite contact Wildeye111 for his subsonic rounds they are just as quite or quitter then FN’s ss193. If you want your PS90 pelt gun quite used subsonic that’s what the cans were made for. All you hear is the slid working.
 

·
Registered
Joined
·
356 Posts
Re: Gemtech G-5 , Advance Armament M4-2000

offshore said:
Maybe this will help. I have two PS90 SBR’s one has the Gemtech G-5 Bilock and the other Advance Armament M4-2000. Both cans are made very well and perform very well... [snip] ...My personal pick is the G-5 it is shorter and 3 sec and it’s on. The grate thing about theses two can is I can put them on my AR’s.
A couple questions:

1.) Do you have pictures?

2.) These are pretty much the two silencers I'm trying to decide between (being they get the best reviews). I plan on having my PS90 cut down into a SBR by Tros, so does that limit my options for cans?

3.) How do both of these work on your ARs? My uncle has two AR-15s and I'd like to be able to use my can on his rifle when we get together.
 
1 - 19 of 19 Posts
Top