A Sub-five-pound AR-15, for When Weight Matters

   11.30.14

A Sub-five-pound AR-15, for When Weight Matters

Most people who take up rifles for hunting, target shooting, defense, and competition are able-bodied adult males. Most people who serve in the military are also able-bodied adults. As a result, not everyone understands just how much they overmatch certain smaller, shorter, and less strong shooters in the ability to handle an 8 pound rifle effectively.To fully appreciate the extent of the weight and reach problem, try aiming a light machine gun like a PKM or an MG34 off hand. That would be a challenge for a 6 foot 180 pound adult man proportional to what a short, lightly built woman would face with a conventional AR15.

M4 carbine, 14.5" barrel.
M4 carbine, 14.5″ barrel.

Certain issues, like excessive length of pull, are easily remedied with shot or collapsible stocks. Lighter barrels and polymer rather than railed forends, flip up sights instead of carry handle all bring the weight down into 6 pound range.

SLR15 Entry model with 11.5 inch barrel
SLR15 Entry model with 11.5 inch barrel

Further reduction of barrel length brings the rifle under NFA regulations. It also decreases terminal effect and increases muzzle blast quite considerably. Not a deal-breaker for SWAT entry teams with select-fire weapons and ear protection, which is a bit of a problem for a home defender.

AR15A2, overall length, 38 inches. Shooter height: 58 inches.
AR15A2, overall length, 39 inches. Shooter height: 58 inches.

The other problem is that 6 pounds is still a heavy rifle for a person with torn rotator cuff, muscular degeneration, or simply insufficient reach and strength. Short shooters have dealt with additional leverage exerted upon them by front-heavy long guns. FN PS90 carbine solves the problem of leverage, but not of weight. Keltec CMR30 will solve the problem of weight, but both it and the PS90 give up 2/3 of the muzzle energy compared to an M4 carbine in the process. What to do if .223 round is to be retained?

I.C.E. Training rifle, a Rob Pincus design produced by MAG Tactical, tried to combine all those qualities into a viable weapon. A 14.5″ light barrel with a fixed muzzle brake gives it the necessary length to avoid NFA restrictions, and magnesium alloy receiver combined with carbon fiber forend bring the weight down to 4.5 to 4.8 pounds with Aimpoint T1 sight installed. A crisp trigger allows practical accuracy around 2MOA in slow fire. The light barrel limits its heat endurance, but the substantial standoff between the forend and the barrel allows rapid fire until the gun overheats instead of when your hands get uncomfortable. While Rob Pincus intended it as a competition and training rifle, I see it more as a defensive or hunting weapon. Few defensive or hunting uses require more than a few shots fired, and certainly fewer than a couple of 30-round magazines this weapon can emit before the barrel profile comes into play.

The shooter is 5 foot tall, 90 pounds counting the concealed pistol. She could hold the rifle plenty steady for a 50 yard chest shot.
The shooter is 5 feet tall, 90 pounds counting the concealed pistol. She could hold the rifle plenty steady for a 50 yard chest shot.

If necessary, a short rail section may be attached to the forend for a light or similar accessories, but the main idea is to keep this rifle light, streamlined, and simple. With the long battery life typical of the Aimpoint sights, it can be left on for months and be instantly available for defensive use at home. For ease of handling, it comes with a slightly extended charging handle and an enhanced telescoping stock, improving significantly on the traditional excessively textured M4 buttplate.

While a sub-5lb bolt actions are easier to make, they lack the recoil amortization of the built-in buffer and tend to be rather less pleasant to fire. They also lack the emergency rate of fire helpful for breaking off a bear or urban goblin charge should the owner run into such an eventuality.

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