Though these guns are forever associated with their drum magazines, it has always been far more common to see a Thompson loaded with a twenty or thirty round stick magazine. This was particularly true after the introduction of the M1 models, during the Second World War. These newly designed models, stripped down for ease of manufacture, were not capable of taking the drum magazines. This was due, in large part, to the cost of the drum magazines, but weight, and the relative fragility of the complicated winding mechanisms were also factors. Millions of M1 Thompsons were manufactured, while the drum capable 1921, and 1928 models numbered only in the thousands.
    The drums could also be quite a chore to load, and maintain, and were fairly difficult to install, particularly in the heat of battle. If the small "Third Hand" used to install the drums was lost, installation could be next to impossible. Drums were also susceptible to denting, overwinding (or lack of winding), and could make the already heavy guns really clumsy to handle.
    The original Thompson stick magazines had a capacity of 20 rounds; for extended firing, the drum magazine was used. When the military redesigned the Thompson for the Second World War, the drums were not considered to be practical. It was also noted that several additional  manufacturing steps were required, to make the guns capable of accepting them. These steps were eliminated from the M1 versions, which served to simplify manufacturing, thus the cut out, and guide slots needed for the drums were deleted from the design. The external magazine latch was also deleted.
    To partially make up for the firepower lost by the M1 incompatibility with the old drum magazines, newly designed stick magazines, introduced in 1942, now had a capacity of 30 rounds. One unique characteristic of both types of stick magazine is the inclusion of a vertical rail at the rear of the magazine body. Though this would not have been needed on the M1 versions, had they been designed with a magazine well, it had been a requirement on the old drum capable Thompsons, because of the interference that a magazine well would have caused to installation of the drum. Thus the newly designed stick magazines would fit the previous drum capable models, many of which were in use by U.S. forces at the time. It would also be possible to use the stock piles of existing Thompson sticks, without modification in the new M1 models. This course was not followed with the introduction of the Thompson's successor, the M-3 "Grease Gun". The M-3 had a magazine well, and used single track magazines, which were much simpler, and easier to manufacture. The comparatively crude, and primitive M-3 never inspired the kind of admiration or cultishness that was lavished upon the Thompson.
    The Thompson stick magazines are of the double column type, much like a modern high capacity pistol magazine; but they require no magazine well. Unlike most high capacity magazines, which are completely encased in their tight fitting magazine wells, those of the Thompson hang out in the open. They are held in place by a partially enclosed slot milled into the gun's receiver. The rail on the back of the magazine fits up this slot, and guides the magazine into place. A catch within the slot engages a hole in the magazine's guide rail, locking it in place. So the catch is on the back of the magazine, rather than the more familiar side, as in most pistol and assault rifle magazines. These magazines are also substantial, and do not have the throw away design of many contemporary designs.
    I mentioned above that efforts were made to retain compatibility between different magazine styles, and the different Thompson firearms; but this was not always perfect. The modern Thompson expects to find a hole for the magazine catch an inch below the top of the vertical rail at the rear of the magazine. All modern magazines are so constructed, but there are some surplus mags which differ slightly. These magazines have the hole just a fraction of an inch too low, and will not lock properly into the firearm. This was done intentionally, by the military, so that the magazines could be fitted to particular runs of rifles, some of which might vary due to wartime production economies. The solution is simply to slightly raise, and enlarge the hole with a file. In many cases, you will find that this has already been done, either by the Army, a factory refurbishment, or a previous owner. If you look at the photo of my stick magazine, above, you will note that the hole for the catch is somewhat oval. Compare this to the photo at left, of an unmodified, WWII surplus, magazine, next to a modified magazine, and you will note that the hole for the catch is round. If you should purchase a surplus stick magazine, which was never issued, and still in the wrap, you may have to perform this little task yourself. The best tool for this is a plain old half round file, though a moto tool might also be used, if proper care is exercised. Using a file, you should check the fit of the magazine after every few strokes. It is very important not to take off too much metal, or the magazine will be ruined, at least for your particular gun. You can always take off a bit more metal, but you can not add it back on again, if you take off too much. I want to emphasize the fact that these magazines are not defective. Having to make this modification is normal, and the magazines were made this way intentionally, so that the magazines could be fitted to any run of Thompsons, made by any manufacturer. As a matter of fact, if you have an older Thompson, this modification will not be needed, and a modified magazine will not fit properly.
    During the clinton magazine ban, the stick magazines were in relatively good supply, and once the initial panic ebbed, they were available at reasonable prices. At the same time, drum magazines were nearly impossible to find, and once found, sold for nearly as much money as the, rather expensive, guns did themselves. The stick magazines are now easily available, very cheap, and are legal in most places. For about $100, I bought a set of seven, shown to the right along side the original stick that came with the gun. All needed modification in order to fit in my gun. This is cheaper than most pistol magazines, and is probably a reflection of the fact that there are millions of sticks out there, made for war time M1 Thompsons, but not too many civilian owned models these days. The drums, too, are more readily available, though in all honesty, the introduction of the 30 round stick, for war use, makes the weight, complication, and expense of the drum a bit silly, and hard to justify. Still, along with my sticks, I have several drums. This is, after all, a Thompson, but more about that in the next section.