RA 17 should be Rock Island Arsenal, 1917 mfg. .30-40 Krag (.30 US, .30 US Govt, .30 USA). Don't know about the "R" stamp on the primer.
US service rifle cartridge from 1892 to 1903, replaced by the .30-03 Springfield, which was replaced in 1906 with the .30-06.
Apparently military arsenals produced some Krag ammo at least through WW I, if I am right and it is Rock Island. I've seen and shot old Remington ammo, marked .30 USA (commercial ammo), and with that headstamp, its not Remington commerical ammo.
All else being equal (and it almost never is) bigger bullets tend to work better.