Answer: The 1785 Immune Columbia pieces were made at Machin’s Mills, and it was not the intention of this minting facility to turn out coins that were “pretty” or even “numismatically desirable.” Rather, their goal was to produce pieces that, when issued, appeared to be worn and indistinct in certain features. The coiners wanted their product to be readily acceptable in the channels of commerce, and worried that sharply struck pieces with perfect detail might arouse suspicion. For them, wear on a coin was desirable, as it implied that merchants, bankers and others had already accepted it as genuine, and passed it from hand to hand.
While the reverse die was complete and contained the full lettering IMMUNE COLUMBIA and the date 1785, the planchets used were of insufficient diameter, and all specimens I have seen have been incomplete in one area or another. As you noted, even the examples shown in reference books, including A Guide Book of United States Coins and in my own Whitman Encyclopedia of Colonial and Early American Coins, all show this feature.
In summary, if there is such a thing as a perfectly struck example, on a full width planchet, I have never seen or heard of it.
