Sam, at an informed guess, WW 680 was a spinoff from a military contract. WW was making the stuff anyway and decided to add it to their canister lineup. Sales could not have been very high since it is such a specialized powder. If the military contract came to an end, and it must have since there is an abundance of WC 680 on the surplus market, and AA 1680 was competing in the canister market, it did not make sense for WW to keep it in their lineup.
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