Great stuff @Slamfire! Okay a couple pics (love the nostalgia).
Muzzle end of a Mk 12 20mm showing blast diffuser and for you aviation buffs that's an A4F Skyhawk. It used a 75 round snaildrum magazine on each gun, loaded in the bays underneath. Links and spent cases ejected underneath. Our biggest problem with those was air leaks in the pnuematic charging system. Pics from July 1985 at NAS Cecil Field.
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Work bench showing a completely stripped Mk 12. If I remember correctly, that receiver was discovered to have a crack at the locking block, and the wood crate in the background was a new gun assembly from the supply system. Locking blocks were NDI for cracks at every periodic inspection interval. Plenty of lube on the bench
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Here's a rack of them in the back shop, all ready for installation.
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Without feeder assembly they weighed 88 pounds a piece and a loaded magazine was pushing 75 or more pounds. I was in good shape back then!
Cool!
