Here are some plastic 38’s.
The green one has what appears to be a wax bullet and the red one is a UPE. Both are battery cup primed. I don’t think they are just color variation. The case wall thickness of the green one is 0.012" while the red case thickness is 0.030". I know Colt sold red plastic 38 Spl wax bullet cartridges (manufactured by Alcan?) but these were not battery cup primed.
Here are two gold colored plastic 38’s. the one is headstamped “PAT PEND” and has a loose fitting paper wad about 1/4" down in the case. The other appears to be a battery cup primed blank (Movie?).
Any thoughts as to who made them and when and for what purpose?