Shortly after getting my SWD M11A1, I got on the list for a MAX-11A/9mm upper for it so that I could add 9mm capability to the .380 gun (this was before I later bought an M11/NINE). A few months later, I was told that mine was ready to ship if I still wanted it. One of the nice things about the waiting lists at Lage Manufacturing is that you don't have to pre-pay and you're under no obligation. But I still wanted it, ponied up the money, and a few days later it arrived. It was such a fun upper to shoot and such high quality, that I got on the list for their MAX-31A upper, which similarly became available a few months later and arrived at my door within days of my payment.
The MAX-31 and -31A are 9mm accessory uppers from Lage Manufacturing for the M11/NINE and M11A1. Other than having an approximately 2" length difference suited to the two different lower receivers, they are otherwise identical. They provide a carbine length upper that allows the shooter to use inexpensive high-capacity 72-round Suomi M31 drum magazines, or Suomi 50-round "coffin" mags. Like the Lage MAX-11 uppers, it also slows down the rate of fire to around 650 RPM (a faster 900 RPM bolt is also available), and in combination with the longer bolt travel, the gun is much more manageable and accurate for short bursts and follow up shots. This platform has been a consistent winner is national submachinegun matches, with good reason.
The upper has a picatinny rail on its entire upper length, lending itself to a variety of sighting options. Most shooters will use sights that would be common to AR-15 platforms. I use an electronic red-dot sight combined with co-witness flip-up iron sights. The 8" barrel has standard AR-15 threads and comes with a birdcage flash suppressor, which can be easily swapped out for a compensator or 9mm suppressor. The forend has a lower rail so that you can attach a vertical grip, and side rails are optionally available for attaching additional accessories to the forend.
Here is the upper as one of mine came from Lage. An M31 drum was included at the time, but now must be purchased separately:
Changing your M11 from its factory configuration to the MAX-31 configuration is as simple as removing the factory upper and replacing it with the MAX-31 upper. It even uses the same retaining pin. In 30-60 seconds, you've changed it into a completely different gun!
It is so fun to shoot that after getting a MAX-31A for my SWD M11A1, I later bought a MAX-31 for my M11/NINE so no matter which of the two guns I may take out to the range, the drum upper is one of the configurations that I can shoot. The "Thompsonesque" feel of shooting a drum-fed submachinegun can't help but put a smile on your face. What's not to love? I've found the quality to be outstanding, Lage customer service second to none, the upper shoots like a dream with all of the different types of ammo I have tried with it, and I've never had a fail-to-fire or feed problem except when I had a malfunction with an old drum, not the upper itself.
When set up with my MAX-31 and MAX-31A, I personally use ACE AKFX stocks with Lage M11 adapters. I use a longer one on the MAX-31A with a folder mechanism so that the length of pull and feel is approximately the same for both guns, even though the M11A1 and MAX-31A upper are each about 2 inches shorter than the M11/NINE and MAX-31 upper. I took this cue from the Richard Lage. Below shows sketches from the Lage Manufacturing website of the MAX-31 on an M11/NINE (with drum magazine) using a shorter rear stock than the comparable MAX-31A on an M11A1 (shown with coffin magazine).
For those not familiar with the 72-round Suomi M31 drums, the photos below show how they look and how the loading configuration inside is set up.
As of this writing (May 2014) they can usually be found at most online sources like Centerfire Systems or Numrich for $20-$45 each, with the price range mostly affected by condition. My personally recommended source is one of the well-known Uzi-Talk/MAC-Talk guys, "Vegas" -- where he has them graded with photos so you know what you're getting, and even "select" grade is well-priced. CLICK HERE to go to his listing at Uzi-Talk. (Updated February 2015: Vegas drums are now sold out, but he still has some spare parts available... Updated June 2016: Centerfire Systems still has drums, but they now sell for $50 each... better quality drums are at Numrich at $60 each).
50-round coffin magazines, which years ago used to sell in that same cost range, are now almost "unobtanium" and if you can find them, they're usually at least $100-$150, but have recently been seen even as high as $250-$350 each. Unfortunately, the 36-round Suomi stick magazines will not work, because they're a double-feed setup where the drum and coffin mags are single-feed. An alternative stick mag has been "developed" by adding a catch tab to inexpensive Sten magazines. This can be read about on MAC-Talk by clicking here or you can buy already converted Sten mags here
A demonstration video by designer/manufacturer Richard Lage can be seen here:
If you've got an M11/NINE or M11A1 and are looking for the best all-around alternative upper for your gun, the MAX-31 is hard to beat, and has recently been released in a MAX-31 Mk2 version that's lighter and more streamlined and includes a variable speed buffer system so you don't have to change bolts to change rate of fire. Highly recommended! CLICK HERE to go to the Lage Manufacturing website.
Want an even more "Thompsonesque" feel to your drum-feed setup? Here is my M11/9 with MAX-31 upper, using a Thompson wood shoulder stock from Practical Solutions, and a Thompson wood foregrip from IMA-USA: