Came across a box of 24 blank 45-70 charges (two of which were missing). Note on box says "CAL. 45/70 BLANK CTGS. FOR LINE THROWING GUN." Manufactured in Oct of 1990 by Naval Co. Inc. in Doylestown, Pa. Last night (4th of July) I decided to shoot a few from my rifle. After firing, the smoke smelled like black powder and the white smoke made me even more suspect. Cleaned the barrel this morning and patches further convined me. Does anyone know if in fact they are loaded with black powder? Still have 16 cartridges left.