Suppressors How should an AAC Tirant 9 seat on a barrel?

SABuzzard

Sergeant
Full Member
Minuteman
Aug 31, 2011
532
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San Antonio, TX
Tax stamps just came through for my SBR 9mm AR and Tirant 9 suppressor.

Barrel is threaded to 1/2x28 and matches the piston and fixed barrel spacer, but the threads are too "deep" to allow the back of the suppressor to seat against the shoulder of the barrel. It spins on and the lip within the piston solidly comes to rest against the muzzle.

Do I need a spacer or have the barrel cut and threaded again? Anybody know if the Tirant can be seated against the muzzle like that?
 
Re: How should an AAC Tirant 9 seat on a barrel?

Here is the right approach:

1. Always ask your suppressor manufacturer.

2. Know the following. Thread-on supressors can thread one of three ways. They can seat on a properly prepared and formed barrel shoulder (most do). They can seat by having the barrel's muzzle seat on a facing within the supressor itself. Or, they can seat on both (a prefered method by some.)

The trick is letting your gunsmith know what the prefered way is by asking the can manufacturer first. If that simply cannot be done, the threading is done with an eye to not reaching into the can, but rather having the can come back and squarely seat on a properly formed barrel shoulder.

The vast majority of all Neilson devices require that the can rest on the barrel shoulder.

<span style="font-weight: bold"><span style="text-decoration: underline">BUT.....that is for reciprocating barrels. Your SBR is a rifle and that makes things more interesting</span>.</span>

You want to take off the Neilson and place on a "static" coupler. Why? Because the Neilson actuation actually wears the spring and the bearing surface (hopefully, broad and substantial.) On your rifle it is simply not needed in any way. Neilsons are for automatic slides and should be saved for such.

My guess? The static mount that you are about to get will allow the threading to disappear into the housing and your coupler will reach back to the barrel shoulder. You do not want to cut back thread on a rifle if you do not need to.

Best.

 
Re: How should an AAC Tirant 9 seat on a barrel?

I really dont think it matters. I had yankee hill thread a cx4 storm, and the tirant 9 is fitting the same way you describe. it works fine, and accuracy is the same. You do know that you have to remove the spring from your piston, and replace that with a fixed barrel spacer when using the tirant on a rifle? Some people dont know that. But, it doesnt change the amount of threads showing. You are still using the same piston.
 
Re: How should an AAC Tirant 9 seat on a barrel?

Thanks for the responses...

I've reached out AAC to see what they say. I'm as curious as to when/if they respond as I am to what the response will be.

Got the fixed barrel spacer installed (replaced the spring with the spacer) but had no impact on the thread length.

Here's a spacer that looks like it could work... www.gem-tech.com/store/pc/Spacer-for-22lr-Silencer-use-on-longer-threaded-barrels-8p472.htm or at least make me feel better.
 
Re: How should an AAC Tirant 9 seat on a barrel?

Pleasantly surprised... Got a quick response from AAC. Actually a couple of responses.

First response...

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Subject: Re: Barrel threading for Tirant 9



Thank you for your email, and for your support of AAC.

The potential problem that I see is we don't know how far in your threads are going into the piston. My first recommendation would be to get your barrel re-threaded so that you have no potential problems.

On Tuesday, when I get back to the shop, I will email you a thread guide to share with your gun smith to ensure proper fit.

I hope that this information helps, and I look forward to helping you get your issue resolved.

Thanks again!

Sincerely,


Brent Taylor
Customer Service
Advanced Armament Corp.

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Mike Mers was cc'd on the message and he later responded -
Second response....

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It is safe to shoot your gun like this.

Please take time and make sure your piston is indexing on the muzzle.

To do this please remove the piston form the silencer and install it on the barrel. Look closely and make sure that the piston is bottoming out on the crown of the barrel. If it does you are good to go.

enjoy

Sincerely,
Mike Mers | Sales Manager
Advanced Armament Corp.

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The piston indexes the muzzle so it looks like I'm good to go.