I found a .50 caliber ammo box today that had several bandoliers of Caliber 30 Ball M2 Garand ammo. One of the bandoliers wad this stuff in it. It's steel-cased Lake City 30 caliber carbine in the stripper clips. The ammunition is dated 1956.
I wasn't aware that they made steel-cased M1 Carbine ammo then.
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