Sunday, June 1, 2014

Box Magazines

In our last post, we studied tubular magazines. In today's post, we will study a type of magazine that is commonly seen in modern firearms, the box magazine.

In the latter part of the 1800s, bullets became more and more pointed (spitzer type bullets) because of better efficiency and accuracy over longer ranges. However, storing cartridges using pointed bullets in a tubular magazine wasn't a very good idea, for reasons we already studied in the previous post. The box magazine was invented to allow safe storage of cartridges of this type. Instead of storing the cartridges nose to tail (like a tubular magazine does), a box magazine stores the cartridges parallel to each other. A spring at the closed end of the magazine pushes the cartridges outwards.

There are two types of box magazine: the internal (or fixed) magazine and the detachable magazine.

Internal magazines are generally seen on bolt-action rifles and usually hold about 5 to 10 cartridges. They can be filled by hand, or more quickly by using clips, such as stripper clips or en-bloc clips to shove in multiple cartridges at a time. An internal magazine is not easily removable from the firearm.

A Lee-Enfield No. 1 Mark III rifle. Notice the internal magazine in front of the trigger. Click on the image to enlarge. Public domain image.

The above image shows a Lee-Enfield Mark III rifle. Note the internal magazine in front of the trigger. This rifle is loaded by opening the bolt on top of the rifle and pushing cartridges into the magazine. The magazine holds up to 10 cartridges. The cartridges can be fed in one at a time by hand, or by using a stripper clip containing 5 cartridges and pushing them into the magazine simultaneously. The video below shows how this is done.

Detachable magazines are designed to be attached and removed from the firearm and can be loaded separately. This allows the user to carry multiple magazines that are pre-loaded with cartridges and quickly switch between them as needed. Detachable magazines are generally loaded at the bottom of the firearm (e.g. most modern pistols, submachine guns, semi and fully automatic rifles etc.), but there are a few famous exceptions. For instance, the Sten and Sterling submachine guns have their magazines attaching to the side of the firearm, and the Bren gun and Madsen machine gun have magazines that attach on the top. Detachable magazines may be straight or curved, depending on how many cartridges they hold and the type of cartridge.

Two detachable box magazines. Left is a 20 round magazine made by Colt, right is a 30 round "High Reliablility" magazine made by Heckler & Koch.
Click on the image to enlarge.
Image licensed under GNU Free Documentation License v 1.2 or later, by user Raygun on wikipedia.

The video below shows how to interchange detachable magazines on a pistol.

The invention of the box magazine is generally credited to two Scottish born Canadian brothers, James Paris Lee and John Lee. In 1878, they invented a rifle, whose box magazine design was used by the Lee-Metford and later, the Lee-Enfield rifles.

The original Lee Rifle prototype. Click on the image to enlarge. Public domain image.

The above image shows the first Lee rifle prototype. The box magazine is visible under the stock, just ahead of the trigger guard. The magazine that this rifle uses is an internal magazine.

Box magazines store their cartridges in columns, either one above the other (single column a.k.a single stack magazine) or in a zigzag manner (double column a.k.a double stack magazine or even quadruple column a.k.a casket magazine). The images below show the different styles of magazines.

A single column (single stack) magazine. Click on the image to enlarge.
Image licensed under the Creative Commons Attribution 3.0 Unported License from Martin Meise at Wikipedia.

A double column (double stack) magazine. Click on the image to enlarge.
Image licensed under the Creative Commons Attribution 3.0 Unported License from Martin Meise at Wikipedia.
A quadruple stack (casket) magazine for a Spectre M4 submachine gun. Click on the image to enlarge.
Image licensed under the Creative Commons Attribution-Share Alike 2.0 License from Evers at Wikipedia

In the above illustrations, notice that each magazine has a spring and a follower piece at the bottom of each magazine. The spring and follower keep the cartridges pushed towards the top of the magazine, where they may be picked up by the firearm's action.

Box magazines can be made of either metal or plastic. In some firearms, the plastic magazines are made of a transparent material, which allows the user to easily see how many cartridges are left in the magazine.

Box magazines are loaded by hand, or more quickly by devices such as stripper clips, en-bloc clips, speed loaders etc. We already studied stripper clips and en-bloc clips two posts ago. In the images below, we see two other speed loading devices designed for M-16 magazines:

A bench loader and a strip loader for M16 magazines. Click on the images to enlarge.
Images are in the public domain.

People who use pistols may be familiar with a device called a "thumb saver", which is sometimes used to load magazines. Basically, a box magazine is usually pretty easy to load by hand, except for when the magazine is almost full. The last couple of cartridges are usually very hard to push in manually and thumb savers reduce the effort required to do this (and prevent sore fingers and thumbs!).

Box magazines have a number of advantages over tubular magazines:

  1. They can safely hold cartridges that have spitzer-type (pointed) bullets, which tubular magazines cannot do.
  2. They can hold a fairly large number of cartridges, compared to tubular magazines. 30 round magazines are very common for rifles, for instance.
  3. If they are made of plastic, they can be made transparent (this isn't always done, but is transparent on some models) so that the user can see how many cartridges are left in the magazine. Since tubular magazines are generally enclosed by the stock of the firearm, the user cannot see how many cartridges are left in a tubular magazine.
  4. The user can preload a bunch of magazines in advance and can quickly switch between them (at least, for detachable box magazines).
  5. It is easier and faster to load or unload a box magazine than a tubular magazine.

Because of these numerous advantages, box magazines are the most common type of magazine used by modern pistols, submachine guns and rifles today.


  1. The Lee-Enfield (and Lee-Metford) magazines are easily detachable, although for the purposes of cleaning and not reloading. Magazine release is inside the trigger guard at the top

  2. James Paris Lee didn't invent the box magazine. There is an earlier patent from 1867 by Walker, Money and Little covering this invention.