appears a patent was filed for a quad stack magazine. Follower is variable geometry which folds out when in the quad stack portion of the mag and folds back in in the double stack portion. Wonder how this will turn out. Speculated that it holds 50 rounds. If it works good, might be fun to have a couple :o
Magpul has just filed a patent application (#20100126053) for a quad stack AR-15 compatible magazine.
The design is quite straight forward. A central partition separates two duel staggered round stacks. Two springs are used, a lower stronger spring and a weaker top spring, which are joined by spring slicer.
The magazine has a constant curve geometry. Interestingly, the transition area (16) is asymmetric in order to stagger rounds correctly.
The follower is very interesting. Two bails (58a and 58b) are spring loaded. When the follower is pushed against the central partition they part and reveal a hole which allows the follower to descend below the partition.
The patent does not reveal what the capacity of the magazine would be. I would expect it would be around 50 rounds.
The patent application comes on the heel of the announcement from Izmash that one of the major features of the AK-200 will be a 60 round quad stack magazine. It seems 2010 or 2011 may be the Year of the Quad Stack Mag!
A quad stack magazine would be ideal for the M27 IAR. I have no doubt that Magpul will eyeing a lucrative contract with the USMC.
Oh great another Magpul product for me to daydream about. I have to say the guys at Magpul really try to outdo themselves at every turn. If they can make it as reliable as the Pmags, then sign me up. Thanks for the post ForTehNguyen, it is appreciated.
Hmmm… this kinda reminds me of the quad stack magazines used on the Spectre M4 9mm SMG. I’d be happy to see this in the future; it’d make a great starter mag.
I REALLY hope this works as well as the P-MAG. This would be perfect for home defense usage on standby. 50 rounds of GTFO on hand w/out a mag coupler or redi-mag.
This design of a magazine has been done before…the AK & the other one that comes to mind (that I cant remember the name) is a pistol type weapon that has this same set up, only in 9mm.
One of the latest topics w/ the M27-IAR is the magazine delivery system that they will use. The C-BETA is the most obvious choice, but if you have ever had one, you know how they are, but I think that this type of mag would only prove positive in the success of the M27, as well as for everyone else…
Not suprised. The first time I read about the IAR my first thought was Magpul better get cracking on a quad stack. I know the AK74 quads suffered significant teething problems but I trust Magpul will get these running right. Can’t wait till the Marine Corps gets their fill and they start making their way to us.
What kind of teething problems did the AK74 quads have? Were they a similar design? Glancing at the patent (with all my years of mechanical training I received with my liberal arts degree) it looks like those spring-loaded bails might be susceptible to getting clogged up with debris.
If it’s close, does the US Patent Office grant patents to a design that’s very similar to something that’s already been released somewhere else in the world? (The EU patent office does not IIRC)
