Thank you dc,dachief and cannonball. I found an image of the bullet and gun.TheCannonballGuy said:Thanks for the very-precise measurement. Converting your millimeters ruler to inches, your bullet is definitely a civil war era .44-caliber Colt "New Model" bullet, manufactured by the Hazard Powder Company (Hazardville, CT), for use in the Colt Army-model revolver.