Home Guns & Ordnance USN Guns: Range Tables, Ammunition & Testing

USN Guns

Range Tables, Ammunition Design & Testing

There can be no set pattern size for any ship as on any given day the sea state is different and the ship’s heading with respect to the waves is different. This changes the pattern size.

As the sea state changes and the ship’s heading changes with respect to the waves and troughs, the bending and twisting of the ship changes. The bending and twisting of the ship changes the alignment of the roller paths of the turret, gun mounts, and directors with respect to each other, and affects the size of the pattern and the range of the MPI of salvos.

The pattern size can only apply to the ship on the day of firing and at the particular ship’s course in relation to the waves on that day. For these reasons the USN did not and could not produce a table that reflected an accurate pattern size for any ship, nor could any other navy.


Note: OP 1457 Range Tables for the 16″ AP MK 8 MOD 0 2700-lb Projectile and OP 1100 Range Tables for the 16″ HC MK 13 MOD 0 1900-lb Projectile are for the 16″/50 guns of the Iowa Class Battleships. Full (service charge) for both projectiles is 6 bags; the total weight of the six bags being 650 lbs.