Tony, wasn't this first done on the old DIVAD program? I seem to recall seeing some inert 40mm VT fuses on a guy's desk at work (LTV back then) back in the 80's. Nobody here remembers if we were subcontracted to Ford on that program or not. And frankly if we were, I can see why noone would want to own up to it. What a disaster.
According to Jane's Ammunition Handbook, the first 40mm Bofors proximity-fuzed ammunition was the PFHE (Pre-Fragmented High Explosive) introduced in 1975 as a part of the Bofi system. The Mk II version came out in 1983.
I do know that prox-fused 35mm ammunition was developed for DIVAD for the Oerlikon guns chosen by a couple of the competitors. This was apparently a US Army requirement, in opposition to Oerlikon's recommendations - they felt that the calibre was too small for prox fusing to be worthwhile, and have since introduced the time-fuzed AHEAD shrapnel ammo for the gun.
With the benefit of hindsight, since the US Army wanted a system in service as a matter of great urgency, the only sensible option would have been to buy the existing German Gepard turret (2x35mm) and drop it on a US chassis. But that was too obvious...
Tony Williams: Military gun and ammunition
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