This 2nd Model Colt Square Back Navy is so early it is actually in, what is recognized as, the 1st Model Square Back range.  There really is no clear demarcation in the serial numbers between the 1st and 2nd Model Square Backs.  It is more or less a transition from one gun to the other.  Either way, the gun is absolutely correct in all respects.  It was actually manufactured in 1850.  All serial numbers are matching to include the frame, barrel, loading lever, barrel wedge, cylinder, cylinder pin, back strap and trigger guard.  The grips are original and "slim-jim" in shape.  The barrel address is the very early variant and mostly intact.  The cylinder still has a considerable amount of cylinder scene and shows the Ormsby signature under the Colt's Patent.  The gun has a very light, peppered texture.  The oxide was cleaned off it years ago but it was not buffed, filed or sandpapered.  Much of the silvery, cased surface is still showing on the frame, hammer, etc.  The nipples are original and the cylinder rotates and locks up fine.  SOLD!!