57 55 J

It the first coastal gun designed and manufactured completely in Finland and was intended to replace the older 57 mm Nordenfelt and Hotchkiss guns, but the design was found faulty and only 11 pieces were constructed.

The desire of the Finnish Navy headquarters operational section to begin domestic manufacturing of coastal and naval guns also influenced the decision to develop 57 55 J.

The prototype, partially based on the older Nordenfelt and Hotchkiss guns, was designed by Engineering Lieutenant Colonel Antero Albert Jokinen and was finished in 1941 in the Helsinki naval base.

[1] When the guns were test-fired in Jyväskylä, it was found that the slide of the semi-automatic mechanism was not strong enough and could bend.

Antero Jokinen was later criticized for attempting to build a "too good" gun, without considering the abilities of the Finnish industry at the time.