Source : Webster's Revised Unabridged Dictionary (1913)

Breechloader \Breech"load`er\, n.
   A firearm which receives its load at the breech.

         For cavalry, the revolver and breechloader will
         supersede the saber.                     --Rep. Sec.
                                                  War (1860).

Source : WordNet®

breechloader
     n : a gun that is loaded at the breech