info found on APG's M4A1 Calliope
- APG has recently stripped & repainted their M4A1 Calliope.
Hidden under the paint, on the right side of the hull just before it
meets the front fender, one can now see that the Lima logo
("LIMA"-inside-a-diamond) is faintly stamped into the hull.
Just below that is "1916."
There were a series of Signal Corps photos taken at the Lima plant
at the outset of production in early 1942.
Some of these photos appear in both Hunnicutt's & Green's "Sherman" books.
In the original prints, the numbers 1003, 1006, 1012 & 1016 can be seen
painted on the hulls of some of the tanks.
Lima was not assigned S/Ns in that range, so the numbers remained
kind of a mystery.
With "1916" coming to light, it now appears that the numbers represent
the Lima build number, added to 1000 - for some reason(?).
In other words, the Calliope was the 916th Sherman built by Lima.
Doing the math, that corresponds to serial number 7320, & indeed,
that is the Calliope's S/N.
AFAIK, the actual ordnance serial number does not appear to have
been stamped onto the exterior of any US-built M4A1's.
However, this "new" number seems to be a valid "back door key" to
the S/N on M4A1s built by Lima Locmotive.
The company built 1655 M4A1s, & I'd be interested to know if the logo
& build number are stamped into the same location on any more of them?
I believe the numbers would run 1001 through 2655.
This is probably impossible to see under all the paint on most surviving
examples, but it was partially visible on the Calliope before it was stripped.
Anyway, if you come across a small hatch M4A1 (or M32B1) in your travels,
please check the area mentioned.
It might be possible to confirm the number correspondence by locating
more survivors, particularly one or two with known, good serial numbers.
Any info, even partial number reads, would be greatly appreciated.