The new Army was a Remington pistol - .44 cal - with a top strap ( the frame & barrel is together opposed to the Colts frame which has a breakdown wedge to connect the frame & barrel and is open on the top, no pice of metal over the cylinder). Used to do the Civil War stuf for years.
Hope this helps
remington 1858 new army picture below
http://upload.wikimedia.org/wikipedia/commons/thumb/4/45/New_model_Army_IMG_3544.jpg/300px-New_model_Army_IMG_3544.jpg