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Fake cans to double as barrel extension for Calif. OAL

6523 Views 20 Replies 6 Participants Last post by  dchang0
I've been wondering about making up the 30-inch overall length requirement in Calif. by attaching a 2.5" butt extension and using a fake can to make up the remaining 2.5". The 4.75" butt extension just throws the hold of the gun way off--it no longer makes sense to have a PS90.

Is it possible and advisable to mount a fake can forward, so that it extends past the muzzle of the PS90? I don't mind cleaning the gun and the fake can frequently, so long as I can shoot it in Kalif.

Thanks in advance for any advice!
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You could mount it farther up but it wouldn't look as appealing
Yes, you would have to in order to make up the difference in length(2 or 4 inches). Coldwar sells a kit where the fake can/barrel extention makes up the whole length issue. It covers the whole barrel plus the 4 extra inches. They said once they would possibly sell just that piece but never really inquired further.

Sounds like you want a '90 really bad :p
I think Hi Desert Dog can just make you a longer barrel. He is a sponsor here.
Wow, I had no idea that there were these other options like making a longer barrel and Coldwarshooters' extra long fake can--freakin' amazing!

aztecw, I think that's the way I'm gonna go. Thanks very much for the link to the pics--I'll ask 'em if they'll sell just the fake can.

I like the idea of making a longer barrel, but the cost is a bit too much. HiDesertDog charges $359 for the "match grade" PS90 barrel that's a couple of inches longer:


It's threaded, so one could install a short 2.5" muzzle brake and meet the required OAL, OR just use the 2.5" butt-extension.

What's really interesting is that HiDesertDog describes making a shroud "similar to original shroud." Maybe all I need them to do is to make a longer shroud rather than actually make the longer inner barrel. It would be the same concept as the fake can but a tighter fit.


(Iceman: Yup, I'm gonna get a PS90 and SOON! That can be done today, but making it Calif. legal may take a bit more time.)
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dchango - Thanks for the link to HiDesertDog's site. I haven't seen that one. But, ouch. Pricey. Extending each end seems like the ideal way to get to 30, so as to not throw off the rifle one way or the other.

But, I spoke to Bob at FN and he advised against replacing the barrel. He mentioned the threads ran opposite. I would guess if you knew that before you started it wouldn't be problem. :-?
Replacing the barrel voids the warranty - I already asked because I wanted to know if short barreling the gun voided the warranty - they stated it did.
D'oh! Forgot about the warranty issues! Yeesh, this is truly getting to be a royal pain in the ass--those legislators up in Sacramento really made this law a supreme annoyance. What's maddening is that criminals who have no regard for the law would simply go out and buy a black market full-auto P90 with impunity. It's as if they have more rights than us law-abiding citizens!

Anyway, it looks very much like the super-long fake can linked to by aztecw is the way to go. Thanks very much for the link--I learned quite a bit about "canceling a flash hider" from some of the later posts in the thread.

This is sorta fun because it's like a giant real-life puzzle that's a combination of mechanical engineering and lawyering. But it's not so fun because I don't have easy access to a rapid-prototyping machine so I can crank out my own solutions to these engi-legal problems.
Well, I called Cold War Shooters and they are out of stock of Sal's barrel extension / giant fake can kit. Sal has so far not responded to my PMs over on Calguns.net, and CWS said that he would likely be unreachable for a while because of some project he is working on.

So, I'm wondering if the CMMG Gemtech fake suppressor can be mounted super-far forward (as forward as it will go) to make up the 4 inches. So far, I haven't found any dimensions of the Gemtech can and the PS90 barrel and muzzle brake so that I could calculate whether it would add 4 or more inches in this manner.

Does anyone have a fake Gemtech that they could mount as far forward as it would go to see if the OAL of the PS90 is over 30 inches? Your help would be very much appreciated, as I couldn't justify spending $140 on a fake Gemtech only to be stuck with it as I buy Sal's solution (which is only sold as a complete kit) for another $125.

Thanks in advance!
That would be a bad idea. The topic hasn't come up for over a year - but the PS90 floats free, and moves while firing. In the past, we have discussed that when using FN's sling that attaches directly to the barrel, one should not put pressure on the barrel when actually firing it.

There is a possibility of damaging your receiver over time by mounting that much weight, that far forward. I wouldn't do it if it were me
Thanks, Shipwreck! I had no idea the outer barrel is not affixed to the upper receiver/frame.
dchango - Just measured mine and with the Gemtech as forward as it can be attacked, it looks like it comes up to about an 1/8 short of 30.

Shipwreck - Now you tell me. Good thing it's only been out shoting once. I did notice the Gemtech weighing more than I expected, but had no idea it would damage the receiver. How about a combo with Critical Demensions 2-1/2 buttstock extension, which would put it back 2-1/2 inches?
Why not.

As for the fake can in the proper place... Several people still have them on and shoot them. I don't know what the long term effects are. Everyone has their opinion on this one. But, the original plan of pushing iit further down the barrel than it is supposed to be - that would probably not be a good idea.
Thanks, aztecw--the Gemtech's out, then. I would like to go past 30" by about 0.25" just to be safe.
While picking up my upper after DROS at Ammo Bros., they showed me a Calif.-compliant PS90 that had a fake can mounted far forward enough to bring the overall length up to 30.25 inches. The can, which I had been considering, is the one that MagazineParts.com carries (the MFI Knights-Armament Style fake suppressor) at http://www.magazineparts.com/productDisplay.php?id=NFS

It may have been modified in order to mount it--I couldn't tell without taking it apart--but it was definitely good enough to work. I've ordered one which will arrive in time for my next day at the range.

Thanks for everyone's help and input!

As we stated in the email, we use the same guys that make OEM parts for Beretta, so if you need a custom part, it can be delivered.
You could try the MFI fake can:


I used this and a stock extention. I just have the sleeve about two inches forward. It will slightly mar the the barrel over time. I had to tighten the screws up real tight. They are plastic lined, but it will wear out over time. My friend is running a gemtech and a critical dimensions extention.
Thanks, btopless330! That's the confirmation I needed. I ordered the MFI can from Mike about two weeks ago--am still waiting for the items to arrive...

If need be, I'll cancel the order and get one from the supplier you gave--thanks!

(I wonder if there's a way to prevent the marring, but anything I could think of would require a synthetic material to be placed between the sleeve and the barrel...)
I originally was going to use some sort of pvc pipe btw the fake can and the receiver. But I decided to just leave it alone. If you don't tighten up the set screws enuf, the sleeve moves back after a few rounds. It's best to check the sleeve to make sure it has not shifted back. Carry the allen wrench with you whenever you shoot.
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