It was the '06 Springfield, the american copy of the Enfield, which in turn was a copy of the Mauser. The Trapdoor was a .47-70 and was loaded from the top thru a "trapdoor", a very weak desing. The '06 was chambered for the .30-'06, the '06 being the year it was adopted by the U.S. Army. The song I'm looking for was in praise of the new round, the flat shooting, hard hitting .30 cal. Ball and the new rifle that shot it, not the old slow 500gr. lead bullet of 1873 and the side hammered rifle that shot it. I shoot both rifles and like each one but if I had to go into Mexico looking for Poncho, the '06 would be the one I would sling.