EOD, case lenght is .878" (22.3 mm), projectil body is 1.355" (34.42 mm) and rotaing band is 1.409" (35.8 mm). The primer is headstamped W. R. A. Co. NEW No 4.
I’ll post some extra information not already published in the IAA article.
The cannon using this rounds was designed by Mexican Rafael Mendoza Blanco during his service with “Los Dorados de Villa” (1910-1917). Some sources said that the solely purpose of this design was to make use of the shells taken from Federal Gral. José Francisco Velasco after his defeat at the Torreón Battle (march 24 to april 3, 1914). Mendoza cannons using 35 and 37 mm shells were already in use during the second Torreón Battle (september 29, 1914).
After the revolutionary forces defeat, records mentions two different Mendoza cannons and calibers:
- “Mendoza” cannon of 37 mm;
- “Mendoza” short cannon;
- “Mendoza” grenades of 37 mm;
- “Mendoza” grenades of 35 mm.
The short 35 mm model is illustrated in the picture below dated 1912, and if the date is correct it could mean that this was an earlier design made expressely for this unique 35 mm shell and that the 37 mm model was a later model using the “common” 37 mm shells taken from Gral. Velasco. However, Francisco “Pancho” Villa was assigned to the “División del Norte” in march 29, 1913 and no Mendoza cannons are mentioned before that date.