14-inch M1920 railway gun

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Railway gun
14-inch M1920 railway gun
Diagram showing gun barrel in elevated, normal and traveling positions
TypeRailway gun
Place of originUnited States
Service history
In service1925–1946
Used byUnited States
WarsWorld War II
Production history
Designed1920
ManufacturerWatervliet Arsenal
Produced1925
No. built4
Specifications
MassTube and recoil band: 230,000 lbs
Length18.1 meters (60 feet)
ShellSeparate loading, HE, and AP
Caliber14-inch (355.6 mm)
BreechInterrupted screw, (step-cut)
RecoilHydro-pneumatic
CarriageRailway truck, 14 axles
Elevation50° fixed, 19° on track
Traverse7° on track, 360° fixed
Rate of fire1 rpm
Muzzle velocity2,650 feet per second (808 m/s)
Effective firing range48,220 yards (44,090 m)
Feed systemHand

The 14-inch M1920 railway gun was the last model railway gun to be deployed by the United States Army. It was an upgrade of the US Navy 14"/50 caliber railway gun. Only four were deployed; two in the Harbor Defenses of Los Angeles and two in the Panama Canal Zone, where they could be shifted between the harbor defenses of Cristobal (Atlantic) or Balboa (Pacific).

History

After the close of World War I, the US Army wanted to incorporate the lessons learned from other railway gun mounts and fulfill coastal artillery requirements for hitting a moving target. An effort to design a more universal mount for the Navy's Mk. IV 14"/50 caliber gun was undertaken.

The primary difference from the earlier Navy versions lies in the M1920 carriage, which could be raised and lowered. Prepositioned fixed mounts were installed at the forts, and the gun's rail trucks could be taken out from under the frame. After the removal of the rail trucks, the gun was lowered and bolted onto a pivot point for rapid 360 degree movement, necessary for tracking ships in coast defense. The M1920 carriage made the gun much more flexible. It allowed for the standard practice of using a curved piece of rail to traverse the gun, and it enabled the gun to be used in a fixed position.[1]

Two guns were deployed to Fort MacArthur in the Harbor Defenses of Los Angeles, with firing platforms at Fort MacArthur and Long Beach. The remaining two guns were deployed to Fort Grant and Fort Randolph in the Panama Canal Zone. The two guns deployed to the Panama Canal Zone could be moved to either coast on the Panama Canal Railway. After World War Two ended, the threat of a massive war was over and the United States scrapped these weapons as well.[2]

Models

The Mk.IV gun was manufactured in two models:

Sighting and fire control equipment

The following sighting equipment was used with the gun:

Support cars

Fate

All four guns were cut up for scrap in 1946.

Gallery

See also

References

Wikimedia Commons has media related to 14-inch M1920 railway gun.