This has all been so very interesting... and forces us to research, which only serves to educate us further!  I Love it!!!

As for the cartridges, I concede that they may be original, but I'm still skeptical based on the lack of a "W" on the bullet... and those flat primers.  Some US military rounds even as recent as the 1960s still had the cupped-shaped primers (I have some HXP M2 Ball dated 1962 with rounded/cupped primers).  I just don't know when flat primers started appearing.  Other than that, they sure do look old, so if they are reloads, they were loaded a long time ago...

Time for more research!