[1894]

I've never seen a cartridge head stamped .45 LONG COLT .
I believe there was a ,45 S&W and a .45 gov't that were shorter length than the .45 colt.
Also , the .45 ACP , and also a short new cowboy action round called the " .45 cowboy special"
Any pics of a head stamp that says .45 Long Colt ???

 

[1894]

I believe it is a term folks used when the shorter S&W and the govt rounds were still in production. It became common terminology . As far as I know , other than a few boxes labeled " long Colt " many years back , the head stamp never changed.

Couple articles ( that add more confusion ) :
Jim Taylor saw it one way
http://www.leverguns.com/articles/taylor/45colt.htm

Paco Kelly saw it another way
http://www.leverguns.com/articles/paco/45coltlevergun.htm