"...a few boxes(?) of these..." Pin fire ammo. 19th Century European stuff.
"...dimensions are pretty close..." The 7.62 x 39 isn't close to a .405 Win. It's rimless and 1.056" shorter for one. The .405 is a rimmed, straight walled, tapered, case that's 2.58" long. Nearly twice as long as a 7.62 x 39 case.
A 7.62 x 54R isn't long enough either. It's .474" shorter, the rim is .024" bigger in diameter and 10 thou thinner. It has a tapered base too.
A.45-70 is too short as well.