I noticed a meme this morning, stressing the well known Finnish Sniper Simo Haya. Like all memes, it is partly true – Haya’s rifle was a Mosin-Nagant. It was also worked on to be competitive in target shooting, and he also used a submachine gun in racking up windrows of dead Russian invaders.

Simo Haya is a well-known name compared to Aimo Lahti. Of course, Finland is a small country, and allied itself with Germany in the second world war, so even the name Simo Haya doesn’t have a huge amount of recognition in the US 80 years after the war. So I will write on Lahti.
I have no doubt that John Moses Browning was our nation’s top gun designer. Likewise, it isn’t hard to put him above Mauser or Schmeisser – Browning worked with everything but bolt actions. Mauser perfected the bolt gun. Still, I would put Aimo Lahti at about the same level as John Moses Browning – an impressive gun designer, limited by his nation’s small size, and more impressively, forced into retirement as part of the deal to end the Finnish-Russian war. In the English language, Kevin O’Brien probably said it best
“The spiteful Soviets, whose troops had been shot full of holes by many Lahti designs, demanded that that the Finn retire from arms design, and he did, living on a pension until 1970. His only child became a Finnish Air Force aviator and perished during the Continuation War.”
The sentiment has probably been better written in Finnish, but I don’t read the language. O’Brien has a lengthy post about Lahti and his accomplishments at https://weaponsman.looserounds.com/?p=15260 .
I’ll include another quote from O’Brien – more to encourage folks to click the link and read the rest of the story. It includes photographs – and does a good job of explaining why I rate the man as the closest to John Moses Browning.
Aimo is little known in the Anglosphere, but his name rings a bell because two of his best-known guns bore his own name: the Lahti M/35 automatic pistol (also adopted in Denmark and in Sweden as the M/40) which combined the natural-pointing grip angle of the Luger with a completely different mechanism, and the Lahti M/39 semiautomatic antitank rifle, advertised for years in the pages of American Rifleman and other 1960s gun magazines. The M/39 was the object of every boy’s envy, later, even if by 1939 it was already marginal medicine on tanks. Lahti would use the same basic mechanism in the beefier VKT 40 anti-aircraft gun, usually seen as a twin mount.
He also co-designed the standard Finnish light machine gun of the Winter and Continuation Wars, the Lahti-Saloranta L/S 26. (It would be replaced by Russian DP LMGs which were captured in vast quantities). He was also responsible for some of the Finnish improvements to the Mosin-Nagant rifle, and for a modified Maxim for aerial and AA use called the VKT. All in all he designed over 50 weapons, counting designs like the M/27 rifle (a modified Mosin).
Lahti’s most influential gun did not bear his name at all. It was the Machine Pistol (“Konepistooli” or KP) 31, the famous “Suomi” (a word which just means “Finland.”) While by 1931 this submachine gun was not entirely revolutionary, we need to bear in mind that the 1931 model was an update of a 1926 model, which in turn was an update of a 1922 run of prototypes. That makes the Suomi, for all intents and purposes, a contemporary of the early Thompson, yielding primacy only to the Thompson and the German MP18.”
There is something I can really appreciate in a designer who comes up with a submachine gun capable of a minute of angle shots at 100 yards – particularly doing it with the tools available 90 years ago.