I bought a nice Colt SAA made in 1887 and am trying to figure out which ammo it takes. It says "38 Colt" stamped on the barrel. At that time there was 38 Long Colt and 38 Short Colt being manufactured. Does anyone know for sure which ammo is correct? Can anyone tell me what the grip is made of? It seems old and worn but doesn't look to me like ivory.