Special Interest Arms - AR-15
Special Interest Arms
New Trecenti

AR-15 and M-16 suppressors in 9mm and 300 BLK.

9mm integral suppressor barrels for AR-15/M-16
*.

Complete firearms also available.

*UPDATE!
New option, now available with billet lowers made to take GlockŪ magazines!
9mm available now, .40 SW, 10 mm and .45 acp very soon.
Pistol versions also available.
Please email to be placed on the pre-order list.

Using the same basic design and baffles as our Thureon Defense units but made to fit the AR platform upper.
Uppers will fit ColtŪ, Rock River, CMMG and most other brands but not Olympic ArmsŪ.
Barrel and suppressor are one unit, so only one tax stamp.

Complete firearms are now available in several configurations.

Integral suppressed barrel only, $700.00 retail for the standard model.
Complete firearm introductory price* of $1750.00 for the standard model.
We are trying to hold this price for the GlockŪ magazine models in all calibers as well.

A local retailer resells these at $2,250.00
Dealer pricing available.


The standard model uses a simple free-float tube without rails, a flat top "smooth side" upper, six-position "Operator" stock and comes with one magazine.
Other types of forward rails can be fitted at additional cost or no charge if supplied by the buyer.


AR9-SC short video. (YouTube)

AR9-SC short Quick-Time video (Download from S.I.A.)

AR9-SC & Thureon SC's video

Our sample AR-15 9mm with an AR9-SC and optional U.S. made Sherluck MarketingŪ quad-rail.
AR9-SC SN No. 1.

Our new 300 BLK "Trecenti"!

The first unit has not only been completed but also put into the hands of unbiased shooters.
More are in production.
Trecenti 300 BLK example.
Typical comments at the introduction were along the line of "I've used office staplers that were louder than this!"

One shooter thought she was getting double taps, she heard the bolt cycle in both directions, but did not hear the shot.
With sub-sonic loads the Trecenti is very nearly as quiet as a De Lisle, except that the AR-15 platform is a "clink-clank" gas operated action.
Shot report is on par with closing the action on an empty chamber, or casual conversation when using sub-sonic ammunition.

These are simple systems, no exotic materials or overly complex parts are used, but they are quite effective.

The "Trecenti" 300 BLK requires a few minor construction differences from strait blow-back designs such as 9mm due to the need for a gas system.
It uses an S.I.A. design integral gas block and tube base to reduce overall length.
Once installed it is normally "Blind pinned" in place to keep it a single tax stamp design.
Two stamp versions are available as an option.
The gas port is adjustable to tune the action for your ammunition, or turn it "Off" to eliminate bolt cycling noise.

The 300 BLK barrel itself is not ported in order to ensure reliable function at 8.2".
Instead a short extension is ported ahead of the support bushing.

Baffles are the same hard anodized aluminum "Step Cone" type as used in our AR9 and Thureon models with a reduced aperture for .30 caliber.
The blast baffle is stainless steel.
The end cap unscrews so the baffles are easy to remove for cleaning.

The integral design has the advantage of providing plentiful internal volume without the need for excessive overall length.
The barrel and integrated tube assembly are 18.50" long.

Supersonic ammunition may be shot but the gas port must be turned down first.
I would recommend removing the baffles to extend their useful life, this integral design is optimized for suppressed use with sub-sonic ammunition.

Standard uppers and lowers are billet 7075 aluminum CNC items from New Frontier Armory with many advanced features not provided on regular production actions.
I strive to avoid imported components, as many parts as possible are made right here in Nevada, USA.
Lightened chrome YMI bolts for use with sub-sonic loads using light bullets are an option at $160.00 additional cost.

AR-15 "Trecenti" 300 BLK flat-top upper from $900.00 depending on rails used and if I supply a lightened bolt.

We now have improved U.S. made parts priceing, so complete "Trecenti" 300 BLK guns are now available from as little as $1,500.00*
*Using a light and comfortable knurled free-float tube, $1600.00 with a YMI quad-rail.
We can install any tube or quad-rail with a 1.75" or greater ID that the customer will supply at no additional charge.
Red-Dot sight not included.
One magazine is included with a complete firearm.

Please email for order form.
Special Interest Arms