Comments by "Steve Valley" (@stevevalley7835) on "IJN Zuikaku - Guide 404" video.

@rhedosaurus2251 A better question is why didn't the Japanese license the 40mm from Bofors? Bofors would license it to anyone. I have read that the Japanese captured some Bofors guns from the Brits, and reverse engineered them, but never built them in quantity. It would make sense for them to move to the Bofors, because the AA gun they were replacing was a license built Vickers 2 pounder pompom, which was also 40mm.
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@Nightdare you are talking about why the Japanese did not switch to the reverse engineered Bofors in 43-44? Could be right. I have heard the Japanese had three different cartridges, in 7.7mm alone. A logistics nightmare, compared to the prevalence of .30-06 in the US and .303 in the UK. Before the war would be a different scenario. The Japanese chose the Hotchkiss 25mm in 35, before it was adopted by the French military. Navweaps gives the design date for the Bofors as 1934, and in service in 36, so it may have been a near miss that the Japanese missed having the much more effective Bofors.
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