Featured PDW Stock Buyer’s Guide Dave Merrill February 23, 2017 0 COMMENT We’ve heard it said, “The shorter and more useless a rifle is, the more a soldier wants it.” To some extent, it’s true that an extremely short rifle will always hold some appeal; we’ll readdress the “useless” portion later in this piece. While, no doubt, someone has built a stubby version of just about any rifle ever made (to include the archaic Mosin-Nagant), we’re going to specifically focus on the AR-series of rifles. One of the easiest ways to reduce the overall length (OAL) of an AR is to simply shorten the barrel. And indeed, legally registered short-barreled rifles (SBRs) have gained in popularity over the years — with barrel lengths getting smaller and smaller as time goes on. However, there’s still more that can be done on the buttstock end of things, but herein is where the AR-15 presents some unique challenges. As you no doubt already know, the operating mechanism of a standard AR involves the inclusion of a receiver extension (more commonly known as the “buffer tube”) and the requisite buffer and spring housed inside it. This adds a considerable amount of length to the overall system. There are some modified rifles on the market that don’t utilize a receiver extension, but they’re outside the realm and scope of this buyer’s guide. Though variations have existed for decades, the personal defense weapon (PDW) stock for the AR-15 is now more desirable than ever. Unfortunately, not all of them are created equally. In order to reduce the OAL, some changes have to be made to the rifle’s operation. This can be accomplished in a few different ways, with some even requiring proprietary bolt carrier groups. Every PDW stock, sans one, in this buyer’s guide necessitates, at minium, an atypical buffer, spring, and receiver extension. Some stocks trade a little extra length for more flexibility, while others strive for the shortest, stubbiest rifle possible. If a proprietary bolt carrier is used, changing calibers or using it in a non-DI-operated AR may be troublesome, and even without adding special carriers, running alternate calibers may not be possible with every PDW shown. If one is considering a PDW project, it should be done with eyes wide open. Due to the unique nature of the buffer/spring combinations used by PDW stocks, fine-tuning of the action almost always takes place on the front end. Usually this comes down to gas adjustment or specific load development; though sometimes gas boosters, such as the Noveske KX5, come into play. As mentioned, swapping calibers can also add a layer of complexity — once we start severely reducing the gas system length, your options get limited quickly. As such, a PDW project can be a joy or an exercise in frustration. One absolutely could finagle a PDW stock on a 16-inch barreled AR-15, but it would look weird as hell. PDW stocks are typically considered for barrels shorter than 10.3 inches, with some even less than 7.5 inches. Regarding the useless aspect: Speaking specifically of 5.56 NATO, it’s indeed true that traditional loads require high velocities to achieve primary wounding mechanics. However, advances in powder and projectile technology have resulted in loads that provide decent performance even in the [sometimes severely] reduced velocity environment of a short-barreled rifle. The TL/DR version is this: A PDW is all about compromise and bargaining. The shorter the barrel, the more considerate one has to be regarding ammunition selection. PISTOLS If you’re running a pistol instead of a legally registered short-barreled rifle, that doesn’t mean you’re completely out of the PDW game. You still have a couple of options from Maxim Defense. The first is their CQB Pistol PDW Brace. The PDW Brace has all of the same features as the Maxim Defense CQB stock except that it sports a rubberized arm brace in place of their PDW butt piece. Another option is the Pistol EXC, also by Maxim Defense. Instead of a rubber brace or their PDW stock, the Pistol EXC includes just the cheek-piece portion of the stock. Both are currently OEM options from different manufacturers, and either can be swapped out for any Maxim Defense stock assembly once your Form 1 clears, assuming you’re going the SBR route in the first place. USING THIS BUYER’S GUIDE Not every PDW stock on the market is represented in this buyer’s guide. There are new examples produced on a regular basis and likely some updated versions of what you see here. But they’re all based on the same theme. Use this guide to determine the most important aspects for you and compare any new options in the future to these established PDW stocks. When assessing overall weights of a system, take note whether a proprietary bolt-carrier group (BCG) is included. Those that don’t include specialized BCGs may appear lighter in the specs, but weights usually even out when this necessary part is added. Some of the stocks have different buffer/spring options, and these will also be noted. All of the lengths and weights provided result from our own measurements not from the manufacturer’s spec sheet. North Eastern Arms Compact Carbine Stock (NEA CSS) OAL Open 8.75 inches OAL Closed 4.4 inches Weight 31.7 ounces Stock Positions 2 Sling Attachment Points 1 (QD-type) Proprietary BCG (Y/N) Yes MSRP $319 URL www.northeasternarms.com Notes: While the NEA CSS certainly wasn’t the first PDW stock for the AR-15, it could safely be considered the one that started the modern AR-15 PDW stock craze. Instead of a separate buffer system, the CSS utilizes a special bolt carrier with an integral buffer. This makes the package smaller, but also means assembly and separation of lowers can be a bear. Both takedown pins on the lower receiver must be removed, and there’s no mechanism to retain the spring since no buffer retainer spring or pin can be used. Because there’s no castle nut to stake, one has to rely on a thread-locking compound or simple hand-tightening to ensure the receiver extension stays in place. The buffer weight can be changed in order to balance the system, but it has to be physically disassembled to do so — a level of difficulty higher than simply throwing an H buffer in a regular carbine. Safety Harbor Firearms Kompact Entry Stock (KES) OAL Open 10.25 inches OAL Closed 4.5 inches Weight 30.3 ounces Stock Positions 2 Sling Attachment Points 2 (slot-type) Proprietary BCG (Y/N) Yes MSRP $260 URL www.safetyharborfirearms.com Notes: The Safety Harbor KES is a different take on the proprietary bolt carrier/buffer. Unlike other one-piece units, the specialized buffer can be removed from the rear of the BCG. The special receiver extension is torqued in place with a very large hex wrench (included), rather than being secured with a castle nut. We found assembly of the receiver halves to be relatively straightforward; push the separate buffer back into the receiver extension while shotgunning the receivers together. But disassembly requires the removal of both pins. Safety Harbor currently has variations with or without QD mounts, and specific versions for the SIG MPX and MCX. Troy PDW Stock Kit OAL Open 8.75 inches OAL Closed 4 inches Weight 29 ounces Stock Positions 6 Sling Attachment Points 2 (QD-type) Proprietary BCG (Y/N) Yes MSRP $499 URL troyind.com Notes: The Troy PDW Stock kit is very similar to the NEA CSS, but with some improvements. Though it maintains the BCG/buffer combination with similar assembly/disassembly procedure, there are many more stock positions available and the receiver extension can be locked down using a hex nut. The Troy PDW stock kit is also noteworthy because it includes a complete BCG instead of a stripped one, and the stock adjustment button is ambidextrous. Maxim Defense CQB Stock OAL Open 10 inches OAL Closed 5.5 inches Weight 23.2 ounces Stock Positions 4 Sling Attachment Points 2 (QD-type) Proprietary BCG (Y/N) No MSRP $395 URL www.maximdefense.com Notes: The Maxim Defense CQB stock is the first PDW stock in the roundup that doesn’t require a proprietary bolt carrier; it also provides the most buffer weight options. Maxim Defense stocks are available with seven different buffer configurations to accommodate a myriad of calibers and cyclic rates: three using shortened JP Enterprises Silent Captured Springs, and four using special short buffers of different weights. Because the Maxim Defense CQB stock doesn’t use a proprietary BCG, take down and assembly is the same as a standard AR-15, though the buffer retention pin and spring aren’t required if using one of the modified JP Enterprises captured springs. There’s no provision for a castle nut, but a standard stock wrench works to tighten the receiver extension. Though two QD-type sling attachment points are standard, the company has additional QD points and positions available as add-on accessories. It’s with noting the LOP is preset with a hex screw and repositioned by pushing a button. MVB Industries Original ARC Stock OAL Open 8.75 inches OAL Closed 5 inches Weight 28.4 ounces Stock Positions 2 Sling Attachment Points 1 (QD-type) Proprietary BCG (Y/N) No MSRP $355 URL mvbindustries.com Notes: The MVB Industries ARC stock definitely has some unique features. First, it features a two-piece receiver extension with dual nesting buffer springs. Though it doesn’t have a proprietary carrier group, the MVB ARC has a buffer that tucks into the rear end of a standard BCG. The receiver extension can be torqued in place with a standard carbine buffer tube wrench. The ARC stock also features a buffer lock button, allowing for standard separation and reattachment of the receivers though disassembly using the buffer lock takes a little practice to master. The example we have is only two-position, but a multi-position version is available. Currently, MVB offers five different buffer weights for the MVB ARC, and specific stock versions for both 9mm and 7.62NATO. Battle Arms Development VERT Stock System OAL Open 8.5 inches OAL Closed 4.75 inches Weight 19.5 ounces Stock Positions 5 Sling Attachment Points 2 (QD-type) Proprietary BCG (Y/N) No MSRP $425 URL www.battlearmsdevelopment.com Notes: The Battle Arms Development VERT stock achieves the shortest OAL of any PDW stock tested that doesn’t require a proprietary BCG. Battle Arms Development accomplished this by using a special short buffer that the carrier collapses into during recoil, allowing that extra little bit of throw needed for complete cycling. The weight is kept down using a composite interchangeable cheek-piece that can be swapped out. Though a standard carbine wrench cannot be used on the VERT receiver extension, Battle Arms Development provides a wrench in the kit. Due to the peculiar buffer design, slightly more of a push is needed to shotgun the receivers open or closed; otherwise, it’s a normal assembly. Though the VERT can be used with a standard BCG, Battle Arms warns not to use the stock with a nickel boron-coated carrier because the coating’s thickness takes up room in the extension tube and could cause damage. Falkor Defense Optimus OAL Open 10.25 inches OAL Closed 5.25 inches Weight 18.29 ounces Stock Positions 4 Sling Attachment Points 2 (QD-type) Proprietary BCG (Y/N) No MSRP $450 URL www.falkordefense.com Notes: The Falkor Defense Optimus is appropriately named — this is definitely a Transformer. The example we have on-hand is a preproduction prototype so some parts of it are “in the white,” and there may be some slight differences on production models. The Optimus features a grooved receiver extension tube and a lower support with the same corresponding grooves. Each groove serves as a locking position for the stock. We found some lower receivers experienced interference from the integral QD points, but once again this is a pre-production model. One unique feature of the Optimus is that after the stock is fully extended, a hinged piece can be flipped out to give you an extra inch of LOP — and the stock can then be collapsed again, if required. However, in order to bring the Optimus back to its shortest state, the stock must first be extended, and the same hinged piece must be locked back under before fully collapsing the stock. Armaspec XPDW OAL Open 10.25 inches OAL Closed 7 inches Weight 23 ounces Stock Positions 5 Sling Attachment Points 1 (QD-type) Proprietary BCG (Y/N) No MSRP $179 URL armaspec.com Notes: The Armaspec XPDW is the only product in our roundup that doesn’t require either a proprietary carrier or buffer/spring system. Hell, it doesn’t even require a special receiver extension. That’s because the XPDW bolts right to your existing setup. Simply remove your current buttstock (assuming that you’re running a Mil-spec six-position tube), slide on the XPDW, and bolt it into place. It doesn’t make the rifle any shorter than a normal buttstock, but instead just provides the look and styling of a PDW.