"Name. United States Rifle (commonly known as the Springfield).
"Cost. $14.40 without the bayonet.
"Barrel. 24.006 inches in length. The muzzle is rounded to protect the rifling. Any injury here would allow gases to escape around the sides of the bullet and destroy its accuracy.
"On the top in rear of the front sight is stamped the Ordnance escutcheon, the initials of the place of manufacture, and the month and year.
"Caliber. .30-thirty hundredths of an inch. Caliber is the interior diameter of the barrel measured between the lands.
"Grooves. The four spiral channels within the bore of the rifle sometimes called rifling. They are .004 inches deep and are three times as wide as the lands.
"Lands. The four raised spaces in the bore of the rifle between the grooves. These lands grip the bullet as it passes through the bore and rotate it to the right about the longer axis. This rotation serves to prevent tumbling and keeps the bullet accurately on its course. This spinning of the bullet also causes it to drift slightly to the right as it passes through the air. The same effect is produced by throwing a baseball with a twist.
"Twist. The spiral formed by the grooves in the barrel of the piece. The twist is uniform and to the right, one turn in ten inches.
"Length. The rifle without bayonet is 43.212 inches long. With bayonet it is 59.212 inches long.
"Manufacture. The United States Rifle is manufactured by the Government at Springfield Armory, Massachusetts, and Rock Island Arsenal, Illinois.