K&M Arms M17S Carbine

posted on May 25, 2016

Bullpup rifles have always held a strange fascination in the firearms community. There’s a definite number of “not in the face” comments—folks are more than a little concerned about setting off a rifle-caliber round in close proximity to their cranial cavities. The flip side appreciates how the configuration makes rifles like carbines, and carbines like short-barrel rifles, making better use of what is traditionally wasted space between the shoulder and trigger.

Of course, the configuration requires trade-offs, as does much in life. Putting the trigger group ahead of the action necessitates a long, fragile linkage that, until recently, resulted in, well, interesting trigger pulls (a friend described one bullpup’s trigger pull as trying to pull through frozen putty). Controls also often wind up in, shall we say, unique locations.

(l.) Beveled for faster magazine changes, finding the mag well’s location may require additional practice. (ctr.) Dispelling the rumor that bullpups have bad triggers, the Elftmann adjustable unit performed well. (r.) A birdcage-style flash hider caps the 17.5-inch barrel, which is threaded to accept other devices.

While bullpups have been around since the post-World War II period, acceptance of the platform really didn’t come about until the 1980s, when various exotic-looking bullpup rifles were featured in various action movies. The Steyr AUG had a big role in “Die Hard” and other action movies like “RoboCop” and “The Running Man,” while the super-futuristic-looking FN P90 appeared in several James Bond-related movies and science-fiction flicks.

When the IWI Tavor SAR hit U.S. shores, though, the bullpup design got a shot in the arm. Sure, a solid community of folks who appreciated the compactness of the design existed, but the Tavor brought the bullpup carbine back to the collective consciousness and reinvigorated the species. K&M Arms decided to update the M17S design with a more modern look and feel, bringing a host of improvements and new chamberings to the decades-old Bushmaster design.

Charging the M17S is accomplished using a non-reciprocating, ambidextrous bolt.

One of the most-noticeable improvements is the excellent Elftmann Tactical adjustable trigger. This is not the standard, long, gravelly bullpup pull by any measure; it is a clean, crisp, light pull that allows greater precision than might be expected. Compared to other examples in this genre—and even the standard Mil-Spec AR-15 trigger—it is light-years ahead.

The handling is really what you pay for when you get a bullpup. The M17S has a 17.5-inch barrel, which is very nearly SPR-size, yet it is significantly shorter than an M4-style carbine with the stock completely collapsed. The design makes a lot of sense for Soldiers who have to negotiate getting into and out of armored vehicles with tight confines, and this ease of handling translates into a carbine well-suited for home defense. If your choice for a bedside gun is a rifle, investigate the size and handling of the M17S.

Optical sights attach easily to the Picatinny rail atop the M17S.

To accommodate ease of transport, the M17S comes with QD-sling-mount sockets on either side of the buttstock. Pop in a QD mount, clip a single-point sling on the M17S and it allows maneuverability you might not have thought possible with a carbine, let alone a near-SPR-length rifle. Snugged tight against the chest, the barrel doesn’t bang against your knees like an M4-style carbine will tend to do.

There are some trade-offs, though. The manual-of-arms is significantly different from the AR-15, so if you’ve invested time and energy training on the AR, you’ll need a transition period to get used to the M17S. Owing to the bullpup nature, everything’s in a different place including the charging handle, bolt- and magazine-release, magazine well and even the safety. Not only is the safety above the trigger rather than behind it, it’s a push-button similar to a Remington shotgun rather than the selector switch common to the AR-15-style rifle.

Again, it’s not a bad configuration, it’s just different. If one is invested heavily in the AR-15-style platform, there will be a few speed bumps in learning to navigate the M17S. While the magazine release uses the same button, it’s located behind the magazine well rather than in front of it—and the magazine well is located behind where you expect it. There’s an ambidextrous release that allows the magazine to be dropped without taking the strong hand from the pistol grip, but it does require the support hand to move. Once again, it’s not a bad manual-of-arms, it’s just different.

On the range, there was one notable surprise. On a single occasion, releasing the bolt via the bolt release resulted in the chambered round firing. The rifle was pointed in a safe direction, so there were no complications, but it was unexpected to say the least. It is quite possible this was the result of a soft primer, as numerous attempts to replicate this scenario failed to repeat it.

While 5.56 NATO is hardly punishing, the recoil pad helps tuck the M17S into the shoulder easily.

Other than that, the only other problem was one failure-to-feed experienced in more than 250 rounds of everything ranging from steel-case plinking fodder to high-end match ammo. Setting the M17S up for a magnified optic was excruciatingly easy—the Picatinny rail allows quick attachment, and the flat design of the buttstock allowed instant verification of level. Getting the scope dialed in for accuracy testing was equally simple, and the rifle proved to be moderately accurate.

Where it really shines, though, is in rapid target transitions. The M17S, while slightly heavier than some M4-style carbines, is balanced beautifully. The bulk of the weight is located by the buttstock, which is tucked in tight against the body. Moving the M17S from target-to-target requires minimal effort on the shooter’s part and, with a good reflex sight or red-dot optic, getting a good sight picture fast is insanely easy.

K&M Arms has done a masterful job of updating the Bushmaster M17S design. It’s a handy, well-balanced carbine that puts rounds where you want them every time, and is a solid platform for a home-defense rifle—or just something to draw looks at the range.


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