The 21in/45 gun from Rick Robertson's Big Gun DOS program

Just for fun, I reran Rick Robertson's Big Gun DOS program for the 21in/45 gun. This is the report:

     Caliber = 21.0 inch (53.3 cm) 
     Shell weight = 5006 lbs (2271 kg) 
     Muzzle velocity = 2574 fps (785 m/s) 

     Relative ballistic performance: 1.00 

     Muzzle energy = 699.2 megajoules = 257647.2 foot-tons 

     Relative muzzle energy: 0.87 

     Barrel length: 45 calibers 


     Elevation          Range        Time      Velocity   Fall Angle 

       2.5 deg        5600 yards     6.9 sec   2330 fps     2.7 deg 
       5.0 deg       10500 yards    13.6 sec   2139 fps     5.7 deg 
       7.5 deg       14900 yards    20.0 sec   1993 fps     8.9 deg 
      10.0 deg       18800 yards    26.2 sec   1882 fps    12.3 deg 
      12.5 deg       22300 yards    32.2 sec   1798 fps    15.8 deg 
      15.0 deg       25400 yards    38.1 sec   1736 fps    19.4 deg 
      20.0 deg       31000 yards    49.4 sec   1664 fps    26.3 deg 
      25.0 deg       35600 yards    60.2 sec   1642 fps    32.8 deg 
      30.0 deg       39400 yards    70.5 sec   1652 fps    38.7 deg 
      35.0 deg       42300 yards    80.3 sec   1680 fps    43.9 deg 
      40.0 deg       44300 yards    89.6 sec   1720 fps    48.7 deg 
      45.0 deg       45200 yards    98.4 sec   1764 fps    53.1 deg 
      50.0 deg       44900 yards   106.5 sec   1807 fps    57.2 deg 


          Armor Penetration - Vertical Belt Armor 

               (Relative armor quality, 1.00) 

               Maximum penetration: 38.99 inches 


     Elevation          Range            Belt       Deck 

       1.4 deg        3300 yards         36 in
       2.6 deg        5700 yards         34 in
       2.8 deg        6200 yards          ...        1 in 
       3.8 deg        8200 yards         32 in
       5.0 deg       10500 yards          ...        2 in 
       5.2 deg       10900 yards         30 in
       6.9 deg       13800 yards         28 in
       7.2 deg       14400 yards          ...        3 in 
       8.8 deg       17000 yards         26 in
       9.6 deg       18100 yards          ...        4 in 
      11.1 deg       20300 yards         24 in
      12.3 deg       21900 yards          ...        5 in 
      13.9 deg       24100 yards         22 in
      15.5 deg       26100 yards          ...        6 in 
      17.5 deg       28300 yards         20 in
      19.1 deg       30100 yards          ...        7 in 
      21.6 deg       32500 yards          ...        8 in 
      22.2 deg       33100 yards         18 in
      23.9 deg       34700 yards          ...        9 in 
      26.3 deg       36700 yards          ...       10 in 
      28.2 deg       38200 yards         16 in
      28.7 deg       38500 yards          ...       11 in 
      31.1 deg       40200 yards          ...       12 in 
      33.6 deg       41600 yards          ...       13 in 
      36.1 deg       42800 yards         14 in      14 in 
      38.6 deg       43900 yards          ...       15 in 
      41.2 deg       44600 yards          ...       16 in 
      43.8 deg       45100 yards          ...       17 in 
      44.8 deg       45200 yards         12 in
      46.4 deg       45300 yards          ...       18 in 
      49.3 deg       45100 yards          ...       19 in 


     Maximum range = 45300 yards at 46.4 deg elevation