long chalk="long shot" ?

[Orin Hargraves]

>Could the phrase "not by a long shot" which is recorded in the 1860's be =
>nothing more than a mishearing of the 1830's phrase "not by a long =
>chalk?"
>
>Sam Clements

Seems likely to me, or perhaps just the conflation of two familiar idioms; but
the Brits still always say long chalk, I believe. Perhaps the prevalence of
American firearms supplied a more compelling image. A similar case is "X has
another think coming" (invariable Brit form) and "X has another thing coming"
(more frequent US form, albeit with many detractors).

Orin Hargraves