Sten Gun Magazines

The British Sten gun used a simple thirty two round box magazine to feed 9mm cartridges into the sub-machine gun. The Sten’s magazine was always something of a weak point and was in fact updated during the war to remedy some of its faults. Sten magazines are still very cheap and easily available (42,000,000 were made during the war) and I have ended up with a number of them that illustrate different variations in this humble magazine:

The Sten magazine was based on the 50 round Lanchester magazine (the two are in fact interchangeable), which in turn was based on the German MP28 magazine. It was a double stack, single feed design that needed a powerful spring to force the cartridges up and into the receiver of the Sten gun. This made the magazine difficult to load without a tool and meant it fed less reliably than a double stack, double feed design like that used in the Thompson. Repeated loading of Sten gun magazines could also lead to the feed lips moving apart, leading to stoppages:

Many different manufacturers produced Sten gun magazines, this means that there are a number of finishes that can be found on the magazines, including examples left ‘in the white’, those painted black and those that have been chemically blued:

To make a Sten magazine the main body was made from stamped sheet steel, folded and welded into shape. A thick steel collar with the feed lips was welded to one end and a stamped metal base plate slid onto the bottom. The base plate is held in by the internal magazine spring and a simple follower is included:

This follower was one of the features to be upgraded. Early magazines did not have the connecting bar to stop the legs spreading apart, this then helped cause jams so was corrected on the Mk 2 design.

The second feature to be updated was the witness holes in the back of the magazine. Early magazines had a series of four holes along the rear of the magazine to allow you to see how many cartridges remained, each hole equating to eight cartridges. These let dirt in and helped jam up the magazine so were deleted on later patterns. A wide variety of designs can be found in the rear of magazines, with holes, flush magazines and small and large ‘dimples’:

Another variation can be found that came out of India, which saw two brass rods inserted into the magazines to turn them into a single stack design. Capacity was reduced to nineteen rounds, but the reliability of the magazines improved.

With magazines produced by an estimated 42 companies across the Empire, there are numerous variations to look out for in the humble Sten magazine, and with prices as low as £7 a magazine from some suppliers, collecting a selection of them would be an interesting and cheap little project.


  1. Interesting read, thank you! I read some site that it was six mags, an other site claimed 10 mags. Do you know how many mags were issued to paratroopers and infantry soldiers with Sten?

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