1880s Frankford .45-70 "R" Marking

What is the meaning of the “R” at 12 O’Clock on a Frankford made .45-70 Round? These are the 2 headstamps I have (on dug fired cases): Any info would be helpful.




R = Rifle

6 & 84 = manuf june 1884

F = Frankford Arsenal

The 45-55 Carbine rounds will have a “C” instead of an “R”.

In later years when the carbine bullet was seated deeper in the case and the rifle ammo started using 500 grain bullets, the two were easy to tell apart. At that time the “R” and “C” were dropped and a triominal headstamp was adopted.

Contract ammo is headstamped similarly. R B is UMC (Bridgeport). R L is U.S.C. Co. (Lowell). R W is Winchester.


Thanks Ray, I knew it would be a simple answer. I also have a Trinominal Frankford 1888 headstamp.