Mossberg 500 Flex

posted on November 19, 2012

I’m not sure when it started, probably sometime in the 1970s with the birth of Generation Me, but somewhere along the lines we became a nation obsessed with individuality. Anyone under the age of 45 or so, and this includes me, has a need to not only be different but also show the world just how different. As kids, we put stickers on everything. Heck, as adults we do the same thing, at once declaring both our individuality and allegiance by customizing everything we own. And this includes our guns.

Don’t believe me? How else do you explain the exploding popularity of the AR platform? Oh sure, smoke-and-mirror marketing and gunwriter punditry claim ARs are functional, reliable and accurate—all true statements, and all characteristics shared by bolt guns. No, ARs sell because they are cool and infinitely customizable, making them the perfect product for an entire generation of gun owners looking to stand out from the crowd.

It was only a matter of time before shotgun makers got in on the action with a modular scattergun system. The first company to do so in a truly new and, yes, unique way is Mossberg with the introduction of its new Flex line of shotguns and accessories. Last December, along with a few other members of the media, I was among the first people outside the Mossberg factory to get my fingers on a Flex during a deer and quail hunt in South Carolina. The combination hunt was designed to illustrate the new shotgun’s versatility, giving us the opportunity to target both animals with the same gun, or the same receiver anyway.

Much like an AR, the Mossberg Flex shotgun is based upon a single base unit built to accommodate a vast array of swappable accessories. At first glance, the 12-gauge receiver in question is familiar to anyone who’s handled a Mossberg over the course of the last half century, because it’s the same used by the company’s venerable Model 500, which celebrated its 50th anniversary in 2011. This standard pump-action has proven its worth in the field and under fire, with millions of Model 500 shotguns in the hands of hunters, law enforcement and military personnel. Basing this new shotgun system on a time-tested receiver design makes the company’s extensive line of replacement and special-purpose barrels fully compatible with the Flex, adding nearly infinite variety to an already versatile platform.

The literal backbone of the modular Flex system is what Mossberg is calling their Tool-less Locking System or TLS—a proprietary connection system that securely locks the receiver and stock together with a hand-operated latch. With what is essentially a simple lift-and-twist motion, the latch releases, allowing for near instant swapping of the stock. Both the six-splined tab that protrudes from the rear of the receiver and the mated slot in the wrist of the Flex-fitted stock are made from a zinc alloy, which Mossberg’s engineers ensure me won’t wear or loosen.

Whether the TLS connection will last for years as claimed I can’t say. I did get to use the gun for a few days in South Carolina, as well as for the final month of Nebraska’s Canada goose season, and the stock and receiver remained tightly connected through repeated shots with everything from deer slugs to quail shot to heavy 3-inch magnum goose loads. It was so tight, in fact, that it took some wrangling, cajoling and good old-fashioned cursing to get the two apart when I wanted to swap stocks. The TLS latch itself also stays tight enough that the lift part of the lift-and-twist action took no small amount of force.

So why would you want to swap stocks so easily? After all, you’ve been using the same conventionally stocked shotgun for years. But have you used that one gun for multiple purposes? Such as bird hunting and deer hunting and home defense? With the TLS, the Flex owner can instantly change from a selection of six different available stock options, including 12-, 13- and 14-inch models, a four-position hunting stock with adjustable comb, as well as a six-position adjustable tactical stock and a cruiser-style pistol grip. The Flex system, along with Mossberg’s multiple barrel offerings, provides Flex owners one-gun versatility that goes from a home-defense to a hunt-ready shotgun in mere minutes.

A button at the toe of the standard hunting-style stock releases its rubber recoil pad, which can then be easily replaced with one of three different available models, each with a different thickness ranging from ¾ to 1½ inches. To me, this offers the most useful benefit of the Flex platform, all the cool customization and multi-gun scenarios notwithstanding. The three recoil pads, along with the three different available stock lengths, essentially offers one gun with nine different length-of-pull possibilities, making the Flex a perfect first gun for children. As the young shooter grows, the Flex grows with him or her.

The customization doesn’t end with the back of the gun. Up front, a button on the forend releases the slide cover. Replace the standard black one with a camouflaged version, or for the tac-minded, a tactical cover with three Picatinny rails and two cut-outs that accept pressure pads for light and laser activation.

As mentioned, the Tool-less Locking System is solid and close-fitting. Out of the box, it takes a bit of practice to pop the latch with minimal effort thanks to some extremely tight tolerances at the factory, but once you figure out the motion required it opens easily. I also found the latch itself loosens up a bit with time, though not so much it becomes unreliable. The recoil pad and fore-end buttons are both easy to operate and snap into place with a tactile click.

Like most pieces of multi-purpose equipment, the Flex is a generalist, good at a lot of things but not excelling in any particular area. Mainly because it’s a pump, it’s not my first choice for quail. But it performed well for me on in-your-face decoying Canadas, where point-and-shoot is the name of the game. I never did get a deer in my crosshairs, but it was cool to come in for lunch and, with a few quick steps, swap my Flex from a scoped and slug-barreled deer gun into a lightweight upland gun for an afternoon of bird hunting. Had I the notion, I could’ve then swapped in a few tactical parts and propped the Flex in my closet as a quick-handling home-defense gun.

Technical Specifications:

Type: pump-action shotgun
Gauge: 12-gauge
Barrel length: 28" ventilated rib, ported
Sights: fiber optic
Stock: synthetic; matte black; LOP 141/4", adjustable
Overall Length: 481/4"
Weight: 71/2 lbs.
Metal Finish: matte black
Accessories: Accu-Set chokes (Full, Mod, IC)
MSRP: $594


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