SIG MMG 338 Program Series

FN America – Mid Range Gas Gun

During last month’s Modern Day Marine Expo we introduced you to FN America’s Mid Range Gas Gun candidates for USSOCOM’s ongoing program.

While SCAR definitely influenced the development of this rifle, a lot is new. It shares an aluminum extrusion upper receiver, modular butt stock and modular lower with the SCAR, but everything is different.

The team went out to the various SOF components and asked what they’d like if FN were to design a new gun. Mostly they heard the common criticisms of SCAR like the lack of non-reciprocating charging handle, proprietary magazines, and so on. FN set out to rectify those issues and more.

Chambered in 6.5 Creedmoor, the MRGG program called for two different weapons: a 14.5″ Assault version and a 20″ Sniper Support variant.

The weapon is modular and you can reconfigure barrel length or even caliber within three minutes by removing three bolts. The barrel and lower handguard come off as a unit. Bolts are now Torx spec rather than Hex to avoid stripping.

Additional modular components include the Forward Assist and Case Deflector along with the Ambidextrous Bolt Release. You can also swap out buttstock and pistol grip.

They re-engineered the lower receiver with a shorter distance between the grip and trigger than found on the SCAR. They also incorporated an AR-style rear charging handle as well as non-reciprocating side charging handles at either side. These can be removed by the shooter if desired.

Additionally, the lower receiver now accepts SR-25 pattern magazines and is made from aluminum. There are discussions of future caliber compatibility by producing a 5.56 lower like is used with the Mk17. All controls are ambidextrous. The gun incorporates a two-stage trigger developed in house.

The guns are both quite accurate. They are seeing 0.65 MOA for the Sniper model and .95 for the Assault. Recoil was extremely light, even for a rifle chambered in 6.5 CM and was very controllable on the full-auto setting of the Assault variant. Additionally, these rifles aren’t destroying optics and other enablers like we have seen with SCAR.

For this program, FN topped off their Cold Hammer Forged barrels with a HUXWRX suppressor.

The guns seen here are earlier prototypes and FN continues to refine the weapon. Hopefully, we’ll see more of this gun as it’s added to the FN lineup. They are also working on a name and hopefully they’ll unveil that soon as well.

10 Responses to “FN America – Mid Range Gas Gun”

  1. Jake says:

    Do you know why they changed the lower from polymer to aluminum? Was it durability or something else?

  2. Czerta says:

    Can you please post the images in their full resolution? Its so hard to get a good view of these.

  3. Nate says:

    I can’t wait to see FN voiding warranties for the use of suppressors if it makes it to the commercial market and they end up using a bad batch of parts in the guns.

  4. Zach r says:

    And the clone wars continued, for there was no one to stand in their way, but yet one rifle, the hk433, could change it all, if only they would let it.

  5. Steve says:

    Seems like they want an AR-10 style platform in 6.8CM but for some reason cannot ask for it.

    My thoughts while reading this:

    The SCAR had captive TORX screws for all quick-change barrel hardware, not hex.

    Despite two being removable, having three charging handles seems like a bad idea from a manual of arms perspective.

    Lower receiver being Aluminum seems like an ask without justification; i.e. ‘it’s metal so it’s stronger’.

    Might as well market this as a SCAR (Gen 2).

    Also – I love this: “…discussions of future caliber compatibility by producing a 5.56 lower like is used with the Mk17”. When the 5.56 lower and caliber kit more or less doesn’t exist.

    • Thatguy says:

      I think he means the receiver screws. Those are torx now from the look of it. The old ones were 2.5mm hex and armorers stripped the crap out of them.

      As far as the charging handles, side charging is def nice shooting prone even if just for that alone.

  6. Nick says:

    So who’s left in MRGG V2? FN, Sig, and KAC?

    • SSD says:

      All three. I’ve also been informed that Larue and LMT were grandfathered in for their performance in the original round.

  7. Zach says:

    Don’t any of you get sick of this platform style ever! Anything that briefly looks other than m4 turns back into it