REAPR – Ohio Ordnance Works' .338 Machine Gun

Matthew Moss
by Matthew Moss
Ohio Ordnance REAPR (Matthew Moss/TFB)

At SHOT Show 2024, Ohio Ordnance Works unveiled the REAPR lightweight medium machine gun. The REAPR or Recoil Enhanced Automatic Rifle is chambered in .338 Norma Magnum and can also be calibre converted to 7.62x51mm.

Ohio Ordnance Works @ TFB:

The gun was developed by Ohio Ordnance Works (OOW) in response to solicitations from the US SOCOM and US Marine Corps for a Lightweight Medium Machine Gun in .338NM. The niche requirement for a .338 gun dates back to at least 2012 with the first Sources Sought Solicitation being launched in May 2017.

Ohio Ordnance REAPR (Matthew Moss/TFB)

General Dynamics initially entered the field developing their .338 machine gun but this design was later divested to True Velocity and since then SIG Sauer have also developed their MG338/SL MAG. The 2017 solicitation is now inactive, however, in 2021 SOCOM (via PEO SOF Warrior, PM Lethality) began seeking an ‘LMG-M’. LMG-M project seeks a gun that can engage targets out to 2,500m and has a similar weight and form factor to an M240B. A contract had been hoped to be awarded by the end of 2022, however, this slipped back to 2025 and now likely 2026.

The aim of .338 machine guns is to fill the gap between the 7.62mm GPMG and the .50 HMG while providing a dismounted, lighter-weight platform that can give the performance of a .50 calibre machine gun.

Ohio Ordnance REAPR with feed tray open (Matthew Moss/TFB)

OOW began work on their gun in 2020 with numerous patents granted on its features. The REAPR is a select-fire weapon with ambidextrous controls on either side of the pistol grip assembly as well as a traditional cross-bolt safety. The pistol grip itself can be swapped out for any AR-15/M16 compatible grip. Robert W. Landies, OOW’s president and one of the designers of the gun, told TFB that with REAPR they addressed a lot of the pet peeves they had with legacy machine gun designs and that they “took a lot of features and amalgamated the best of them” when designing the weapon.

Intriguingly, the gun uses a roller-delayed operating system, similar to that of the MG45, this means the opening of the action is slowed by rollers but does not fully lock. Post-Second World War Two this system had some influence on a range of designs including the SIG MG 710-3 and a host of Heckler & Koch weapons. The gun uses a pair of springs on dual guide rods and has a 600 rpm rate of fire. The weapon can be field stripped without tools. To remove the action a pin at the rear is removed which allows the butt stock and rear of the receiver to be removed with the springs, guide rods and bolt sliding out of the receiver.

Dual-mount Ohio Ordnance REAPR (Matthew Moss/TFB)

It has a side folding stock, designed in house with B5, with a shoulder rest and an adjustable cheek riser. B5 also provided the REAPR’s P23 Grip and M-LOK rail covers. According to OOW the REAPR weighs in at 26.8lbs and has an overall length of 51.7in (131cm) when the stock is collapsed, 54.5in (138cm) when deployed and 44in (112cm) when folded (it can fold either to the left or right). For use when mounted on vehicles or aircraft, the stock can be removed and a spade grip kit can be fitted. There is also a rail-mounted removable carrying handle.

A key feature is the gun’s barrel quick-change system, this can be done with one hand by the operator. The change can also be done with the bolt either in the forward or rear position. The patented system uses 2 opposing groups of 5 interrupted threads, this allows the barrel to be released with just a 90-degree turn. To remove the barrel, the operator grasps the barrel cover, pushes the barrel rearward towards the receiver, and then turns the barrel 90 degrees to disengage it. The REAPR can be mounted with a suppressor, it has been seen paired with cans from a number of different manufacturers.

.338 REAPR in a backpack (Ohio Ordnance Works)

Another feature is that the entire system can be broken down into 3 pieces within 10-20 seconds. It can be packed away with the barrel at 24.5in (61cm) being the longest component. The REAPR has a one-piece steel receiver and an aluminium hand guard with M-LOK slots, which can be removed via a pair of catches. The gun also has MIL-standard mounting points for either tripod or pintle mounting. Another key, patented, feature is the gun’s feed tray which can slide out to the side of the gun for loading and clearing, this allows the operator to use optics with a larger continuous footprint. SIG Sauer addressed this issue by having a cover which hinges to the side. The REAPR’s direction of feed can be flipped either left or right and ejection is through the bottom of the receiver. OOW note that the gun has a mounting interface for an ammunition pouch on the left side of the receiver but are considering adding one to the right side but are waiting on feedback from users.

Helicopter-mounted Ohio Ordnance REAPR (Matthew Moss/TFB)

OOW say that the REAPR is currently available for ordering in test quantities but full volume production is set to begin in April 2024. It will be interesting to see how the LMG-M programme progresses.

Matthew Moss
Matthew Moss

Managing Editor: & Overt Matt is a British historian specialising in small arms development and military history. He has written several books and for a variety of publications in both the US and UK. Matt is also runs The Armourer's Bench, a video series on historically significant small arms. Here on TFB he covers product and current military small arms news. Reach Matt at:

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5 of 31 comments
  • Takirks Takirks on Mar 08, 2024

    Someone is going to have to explain to me why the hell we're spending all this money on newer and betterer machineguns to overcome "overmatch", when the real problem actually resides in the fact that you're just not going to get better results than we are right now, firing these things off of PFC Schmedlap's shoulder and a bipod...

    You want to fix machinegun fires and delivery thereof? You need better tripods and supporting equipment. Most of the gun teams going into Afghanistan did not have their own binos or rangefinders; their tripods were primitive-ass M122/192 designs we first put under the old M1919 series. Which are not adaptable to the terrain, do not deploy quickly, and are intended almost entirely for fixed defensive positions. Nobody trains on using tripod-supported fires dynamically, any more. You want to reach out and touch someone much past 800m? You need a tripod under your gun, and it really, truly ought to have a damn periscopic sight on it, to keep the gunner's head below the line of sight/fire.

    I'll believe we're on the way towards fixing the problems we have once I see some money going into better tripods and support gear, as well as actual training for the gun teams and leadership. Most US soldiers have no more idea of how to correct fires with a mil reticle and the T&E mechanism than an orangutan has about quantum physics, and that's just because we've forgotten 90% of what we once knew about machinegunnery...

    • Andrew Andrew on Mar 13, 2024

      @takirks Couldn’t have said it better myself.

  • DanMcKraken DanMcKraken on Mar 10, 2024
    for all the range commandos who think fluting and dimpling is useful

    • See 1 previous
    • Andrew Andrew on Mar 13, 2024

      @DanMcKraken That’s the stupidest statement I’ve read on this subject yet. Yeah, man, only range commandos want lighter barrels that minimize tradeoffs. Only range commandoes use Mk46s.