Looks like 3ply to me.

Cam

From what I have been told 1939-ish is the cut off date when a lot of the drum companies went from solid steam bent shells to 3-ply shells...I agree that it's probably a 6.5 x 14 shell, sometimes it's tricky when you measure with heads on, the more that the heads are stretched the more of an illusion of a shallower depth shell...solution...pop the heads or refer to the catalogs.

Mike Curotto