General Information: The Model 1923 French helmets exported to Yugoslavia were distinct from the M23 helmets produced for the French army in the interwar years. Like the Spanish export French M26s they were made with inferior non-manganese, magnetic steel. The export M23s also had a rolled rim, rather than a separate rim piece welded to the edge. In addition, the Yugoslavian export M23s had slot, or oval shaped vents rather than the eight-holed vents typical of the domestic used French M23s. Finally, the Yugoslavian helmets were factory painted green/khaki rather than blue. Regarding the last two features, however, there are examples of factory green/khaki painted French M23s and French M23s with slot vents, although this was not the norm.
Most surviving examples of the Yugoslavian M23s have the oval badges, rather than cut-out badges. Yugoslavian M15s, on the other hand, had cut-out badges more frequently than the M23s. Note that there are at least two different versions of the cut-out badges: one has flat edges on the bottom, and the other has rounded edges.
One of the reasons for the rarity of the Yugoslavian Adrians, both M15s and M23s, is that stocks of these helmets were appropriated by the Bulgarians after the German led invasion of Yugoslavia. They were converted for Bulgarian military use by removing the badges, repainting, and refitting the helmets with Bulgarian made liners.
Displayed Example: This particular specimen surfaced in Bulgaria in 2011. I bought it on eBay. The helmet has the rarer version of the Yugoslavian badge – the cut-out version with rounded edges at the bottom. In my collecting career I have seen just two helmets like this piece. One identical M23 sold at auction recently. The other one is in the collection of a collector colleague. That one was a Bulgarian reissue with the badge removed, but you can see the outline of this type of front plate. It is a rare object. Recently, however, I found two period photos of Yugoslavian solders with this particular version of the M23 (see photo above).
The helmet has no manufacturer stamps in the dome, but there are two size stamps in red ink: Б 1 and 57. The “Б” is a Cyrillic “B.” The M23s issued to French armed forces were produced in three sizes: B, C, and D. There was no size A as with the older M15s. Each of the three sizes of shells could accommodate three different sizes of liner as follows: Size B = 54, 55 and 56 cm, Size C = 57, 58, and 59 cm, Size D = 60, 61, and 62 cm. This replaced the scheme for the M15s which was as follows: Size A = 54, 55, and 56cm, Size B = 57, 58, and 59cm, Size C = 60, 61 and 62cm.[1] The French helmets sometimes have redundant numberings for the sub-sizes. For example, a B1 corresponds to a 57cm, a B2 corresponds to a 58cm, etc. This Yugoslavian export version of the M23 with a size B shell and a size 57 liner, follows the sizing protocol used on the M15s rather than that used on the M23s issued in France. Interesting? I thought so.
Collector Notes: These are faked, of course. Reproduction badges are available on the internet and unscrupulous sellers offer their fraudulent Yugoslavian Adrian helmets to unwary buyers. One obvious thing to look out for are French Model 1926 helmets with Yugoslavian badges. As far as I know, no such configuration existed in the World War II period.
* From the personal collection of Reinout de Waal. http://warhelmets.weebly.com/model-1915-helmet.html
[1] Hennequin. pp66 & 123
Steel Helmets of the World Wars 