It has been my experiance from collecting ammo that if an old cartrige has a canellure near the base of the bullet, it is a smokeless cartige. If it does not, it is a black powder round. Also if it has an "extractor" grove it will be a web head, and if no grove it will be a baloon head case.
That does't hold true with modern brass, but does for ammo made in the first half of the last century.
Winchester, Remingon, U.S. Cartiridge Co. and others sometimes stamped their primers with a symbol. Usually The first letter of their name.
Winchester = W, Remington = U, U.S. Cartirige Co. was an intertwined letter U and S.
That does't hold true with modern brass, but does for ammo made in the first half of the last century.
Winchester, Remingon, U.S. Cartiridge Co. and others sometimes stamped their primers with a symbol. Usually The first letter of their name.
Winchester = W, Remington = U, U.S. Cartirige Co. was an intertwined letter U and S.