13.2x99mm Japanese Hotchkiss "E 1-III 13"


#1

Does “1” in 1-III indicate 1941? This one is un-fired with original projectile. How common are these? The 1st time I bump into these.
image


#2

13 = 13.2mm Hotchkiss
1 = 2601 = 1941
III = september-december
’E’ = Yo = Yokosuka
Red primer annulus = tracer
"Japanese Ammunition 1880-1945, part 1, Ken Elks"