SIG 716, SIG MCX and SIG 556 Xi: An Afternoon Of New Rifles At The SIG Academy

    When we arrived at the SIG Academy and saw all of the stacked hard rifle cases at our range we had a pretty good idea this was going to be a fun and informative afternoon. We weren’t wrong either! There were suppressed MCX multi caliber carbines, the SIG 556 Xi, the SIG MCX and the SIG 716. Several of the models were in a pistol configuration using the SIG SB15 arm brace.

    SIG_SAUER_SIG_MCX_Multi-Caliber_AR_Assault_Rifle_Carbine_SBR_300_Blackout_300BLK_Suppressed_Kevin_Brittingham_Thumbs_Up_and_Smiling_SIG_SAUER_New_Media_Writers_Event_David_Crane_DefenseReview.com_DR_1-660x330 (1) copy

    Photo by David Crane

    Before I start with the various rifles let me introduce Kevin Brittingham. Kevin is standing to my right in the photo above. Kevin is a pivotal figure in the story of many of the rifles we fired that afternoon. For those that don’t know, Kevin is the founder and former owner of AAC. He sold AAC to Remington and now works for SIG designing and developing suppressors and features of the guns that use them. Kevin is also the creator of the AAC Honey Badger.

    In the photo I am holding the suppressed SIG MCX which we had just fired. This MCX is chambered in 300 Blackout. You’ll note the suppressor has no finish on it. This is because it was put together and brought straight to the range from the factory. The factory did not have enough time to apply a finish. You are probably wondering why Kevin has such a big smile. I had just told him this was the quietest centerfire rifle I’d ever shot! Naturally he was happy to hear that. At 118 decibels he has a right to be happy.

    In this video I am firing the SIG MCX with super-sonic ammo (it obviously makes the gun much louder than firing sub-sonic ammo).

    This time firing sub-sonic ammo:

    The MCX is a multi-caliber carbine firing the 5.56, 300 Blackout and 7.62×39. Caliber changes can be made in the field in a very short time. The suppressor is the screw on variety. There are three buttstock designs. There is a standard M4-style stock, an MP5-style stock and a third design, which I was firing called the SAS. The final complete specifications for the MCX are not yet available.

    The next model we shot was the SIG 716 pistol in 7.62×51. Now this pistol was fun to shoot but I could not really get excited about firing it as a pistol.  I did find it comfortable to shoot using the brace as a stock but it does have a bit more recoil than your standard .308 rifle.

    Firing the SIG 716:

    Then we have the one and only writer willing to continue shooting the 716 using the SIG brace.

    Sig 716 in 7.62x51

    SIG 716 in 7.62×51


    Action Semi-Auto
    Operating System
    Short stroke pushrod, rotating Bolt
    7.62 X 51 mm NATO
    38.3 in – 31.1 in / 972.8 mm – 789.9 mm
    Trigger Type
    Trigger Weight
    7.6 lbs
    Barrel Length
    16 in / 457.2 mm
    1 in 10″
    Number of grooves
    w/out Mag 9.3 lbs / 4.22 kg
    Mag Capacity
    20 Rounds
    Mag Type
    Magpul PMAG
    Accessory Rail
    Short stroke pushrod operating system with 4 position gas valve, Quick-Detachable Ambi-Sling Mounts, Flip-Up Front and Rear Iron Sights, Ambidextrous Magazine Release

    The last rifle is the SIG 556 Xi Russian chambered in 7.62×39. It is also available chambered in 5.56mm and 300 Blackout.

    Firing the SIG 556 Xi in 7.62×39:


    Caliber 5.56mm NATO
    Overall Length 35.875″
    Length w/Stock Folded 27.1″
    Barrel Length 16″
    Rifling 1 in 7″
    Sight Radius 18.1″
    Forearm Polymer
    Stock Type Swiss folding
    Weight w/o Mag 8.2 lbs
    Operating System Gas Operated, Rotating Bolt
    Mag Capacity 30 Rounds
    Features Rotary Diopter Sight
    MSRP $1,266.00
    CA Compliant No
    MA, NJ, NY, CT Compliant No

    At the end of the day it was time to blow off some steam by doing some building clearing exercises with simunition rounds.

    I have to say the several days spent with the folks at SIG was a great learning experience. It is my sincere hope that the articles I’ve presented to the readers have been informative and enjoyable. If there is any information you would like which has not been presented in these articles feel free to contact me in the comments below and I will try to answer your questions.

    Late News From SIG:

    I just recieved an email from SIG announcing a micro website that will allow readers to peruse the new model rifles as well as the SIG 320 pistol. You’ll be able to click on each gun and see what options are available as well as how they look on the gun you choose.

    As you know, there’s a lot to take in, option wise, with each firearm. Here’s a handy guide showing all the innovation and tech that went into each product, as well as a breakdown of the options. So, if there was any confusion about a SIG MPX vs a SIG MPX-K or SIG556xi Russian vs SIG556xi Carbon Fiber… or any number of combinations…. Here’s a tool to help figure it all out. Plus, it’s just cool to see all the parts.

    SIG Evolution Website

    Screenshot of the new SIG micro website

    Screenshot of the new SIG micro website

    Phil White

    Retired police officer with 30 years of service. Firearms instructor and SRU team member. I still instruct with local agencies. My daily carry pistol is the tried and true 1911. I’m retired as associate editor since December 14th 2017. My replacement is my friend Pete M email: [email protected] you can reach Pete for product reviews etc.