Hehe... I'll take GSh-301 - at only 46 kilos it's firing 400g 30mm rounds at 1,500 RPM

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Alternatively, one can go for a heavier GSh-2-30 - two barrels, 3,000 RPM at a smidgen over 100 kilos.
And if one wants to go truly bananas - why not try the amazing GSh-6-23? It'll deliver trusty 23mm rounds at 10-12,000 RPM?

Comes in a MiG-31 packaging so can be rather cumbersome if you want to take it duck hunting or something

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