SIG SAUER’s adding a suppressed upper receiver to their lineup: the SUR300. The new upper — chambered in the ever-so-chic 300 blackout (300blk) — fits the SIG MCX and a standard AR15 lower. The MCX upper has some cool features:

– 6.75” Cold Hammer Forged Barrel

– Permanently Attached 19 Baffle Titanium Suppressor

– Free Float M-lok Handguard

– Short Stroke Gs Piston

– Tunable Gas Block

– Cycles Sub and Super Sonic Ammo

It also comes with SIG’s Matchlite Duo two-stage trigger, as well as an adapter that lets you remove the buffer tube and accept SIG 1913 folding stocks. Bolt and charging handle are included.

From sigsauerguns.com:

“This is a new OEM Sig Sauer MCX Conversion Kit that includes an integrally suppressed MCX upper receiver, adapters to convert the lower receiver to accept the MCX upper receiver, and a Sig Sauer two-stage trigger. The trigger installation is required to ensure proper operation of the MCX upper receiver. Using your existing trigger is not recommended and may lead to malfunction.

The suppressor is pinned and welded meaning that the overall length is just over 16″. Putting this on your rifle will not make it an SBR.

Note: All NFA Rules apply. This item will require a Form 3 transfer to your local dealer and then a Form 4 transfer to you. Make sure you can legally own this item before purchasing.”

Specifications:

SKU: UAMCX-9B-300B-SRD

UPC Code: 798681605811

Caliber: .300 Blackout

Manufacturer: Sig Sauer

Sights: None

Frame Finish: Black

Barrel Length (in): 16.8 in OAL

Accessory Rail: Not Applicable

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