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"Home in" predates "hone in." Another example of usage-driven changes in our language.
According to Mirriam Webster dictionary:
Main Entry: hone in
Function: intransitive verb
Etymology: alteration of home in
Date: 1965
: to move toward or focus attention on an objective
Usage: The few commentators who have noticed hone in consider it to be a mistake for home in. It may have arisen from home in by the weakening of the m sound to n or may perhaps simply be due to the influence of hone. Though it seems to have established itself in American English (and mention in a British usage book suggests it is used in British English too), your use of it especially in writing is likely to be called a mistake. "Home in" or in figurative use "zero in" does nicely.