I at all times favored the concept of folding shares, however being a diehard AR man, that wasn’t usually an possibility. Until you went with one thing like a LAW folding buffer system. Due to bufferless uppers from Foxtrot Mike and Brownells, although, I can lastly be part of the folding inventory crowd, too. B5 Methods dropped its Modular Platform Inventory earlier this yr, and I made a decision to snag one and see what they have been all about.
The Modular Platform Inventory from B5 Methods
The B5 Methods Modular Platform Inventory (MPS) is a rugged and extremely adaptable inventory. It options an integral left-side folding metal hinge for compact storage and transport. The MPS gives a 2 1/4 inch collapsible size of pull adjustment for a customizable match.
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The adjustable spring-assist cheek piece provides 1/2 inch of peak for correct sight alignment. It’s simply manipulated by pulling again and both pushing up or down. The MPS is made out of sturdy composite supplies with color-matched metal {hardware}.
The inventory comes with a cushioned, non-slip buttpad for enhanced shoulder contact. It helps ambidextrous use with mounted sling mounts and metal anti-rotational fast disconnect (QD) sling mounts. The inventory attaches securely by way of a 1913 Picatinny mount. It’s accessible in Black, Wolf Gray, Flat Darkish Earth, Coyote Brown, and OD Inexperienced.
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Weight is simply 16.8 ounces, and it measures 8.06 inches lengthy, 1.76 inches broad, and 4.67 inches excessive. Like all B5 Methods merchandise, the Modular Platform Inventory is made within the USA.

Not Simply For AR’s
Whereas I’m at all times a little bit AR-centric, the B5 Modular inventory will match on something with a Picatinny rear mount. This opens it as much as any variety of pistol-caliber carbines. It should additionally work with .22 Rimfire AR’s since they don’t want a buffer. It even works on shotguns.
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I initially used the MPS on my KE Arms/Foxtrot Mike SBR construct. It labored extraordinarily effectively on that rifle. The SBR folded to a really compact 23 3/4 inches with the inventory folded to the facet. The inventory sat excessive sufficient that you possibly can nonetheless entry the grip, set off, and hearth controls when folded as effectively. That means that you can hearth the rifle with the inventory folded if want be.

Prolonged, the lock-up is stable and feels such as you’re firing with a set inventory. It’s way more steady than a lot of the AK facet and beneath folders I’ve used up to now. The rubber butt pad seats firmly in your shoulder pocket. The inventory simply adjusts for size of pull as effectively. You may shortly adapt it for arm size, physique armor, or heavy clothes use.
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Mossberg 590 Match
B5’s MPS was a very good match on the KE/FM construct, however I had different long-term plans for that one. I made a decision to see what else I might use it for from my assortment.
After I picked up the KE Arms decrease, I additionally obtained a Picatinny adapter for the Mossberg 500/590 collection shotgun. Whereas I’ve been tempted to Kind 1 my Mossberg Shockwave, I made a decision to run it on my outdated 590A1 for now.
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My 590 has a 20-inch barrel, so with a set inventory, it’s a fair-sized gun. Including a folder makes it a little bit extra compact for storage within the Jeep. I put in the KE Arms Pic adapter and added the B5 MPS, together with a B5 P-Grip 22, to the shotgun.

The KE Arms adapter put in simply with the included bolt and lined up completely with the Mossberg Receiver. The B5 grip is hooked up with a typical AR grip screw, and the Modular Inventory is bolted to the rear Pic rail. Whereas the inventory is inline, I used to be nonetheless in a position to comfortably use the manufacturing unit ghost ring sights on my 590A1.
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The opposite factor I attempted the MPS on was an AR decrease I’ve fitted with a Picatinny rear rail. I exploit the decrease with a brace and my Solo 300 pistol higher. It additionally works with a wide range of rifle uppers and my CMMG .22 conversion package.
You don’t want a buffer system with the CMMG conversion, so you should use any .223/5.56 higher. You simply must swap out the bolt and magazines to shoot .22LR, then.
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Because the MPS installs on the Pic rail, it’s simple to swap forwards and backwards between it and a brace. That lets me readily swap between rifle and pistol configuration with that decrease. It began as a stripped decrease, and is registered as such, so it’s kosher to swap forwards and backwards to correct authorized configurations.

Wrap Up
With B5 System’s Modular Platform Inventory, you get the entire benefits of a side-folding inventory, with the capturing properties of a set inventory. It has an MSRP of $200.00, which is aggressive with different inventory options available on the market. You probably have a rifle, shotgun, or PCC with a Picatinny rail and wish one thing extra substantial than a skeletonized inventory, the B5 Methods Modular Platform Inventory is a really viable possibility.
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