Dahlgren Gun - Dahlgren Rifled Guns

Dahlgren Rifled Guns

Dahlgren designed several rifled muzzle loading cannon, as well.

20-pounder rifle: An entirely bronze gun that was popular and was the only Dahlgren rifle (other than the 12-pounder boat howitzer) that continued in service after the American Civil War. Crew of six and a “powder-boy” firing a 20 lb. shell in front of 2 lb. of powder it had a range of 1,960 yards at a 6.5° elevation.

30-pounder rifle: These guns were iron with bronze trunnions and trunnion bands. They were cast at the Fort Pitt foundry and the Washington Navy Yard. In February 1862, Dahlgren recommended that the first 13 cast at Fort Pitt be withdrawn because the iron was inferior. One 30-pounder rifle was mounted on the USS Harriet Lane.

50-pounder rifle: These guns were typical Dahlgren rifles—iron with bronze trunnions and trunnion bands. They were apparently a popular design, although by the end of the war it had been supplanted by the 60-pounder Parrott rifle, which continued in service after the American Civil War. A photograph of Admiral Dahlgren leaning against a 50-pounder rifle may be found at the beginning of this article.

80-pounder rifle: The first 80-pounder was cast at the West Point foundry with trunnions. Subsequent rifles were cast without trunnions and bronze trunnion band and trunnions were added. The gun was initially well received but soon showed a tendency to burst. The USS Hetzel, a converted Coastal Survey ship armed with 1 IX-inch Dahlgren and 1 80-pounder Dahlgren rifle was engaged in the bombardment of Roanoke Island in support amphibious landings, when the following entry was made in her log for February 7, 1862: “At 5:15, rifled 80-pounder aft, loaded with 6 pounds powder and solid Dahlgren shot, 80 pounds, burst in the act of firing into four principal pieces. The gun forward of the trunnions fell on deck. One third of the breech passed over the mastheads and fell clear of the ship on the starboard bow. One struck on port quarter. And the fourth piece, weighing about 1,000 pounds, driving through the deck and magazine, bringing up on the keelson, set fire to the ship. Fire promptly extinguished.” (Ripley 1984, p. 106)

150-pounder rifle: The 150-pounder was a typical Dahlgren rifle with a cast iron barrel and a bronze trunnion band and trunnions. Although the test firing was successful the guns were not placed in service, because Dahlgren doubted the quality of the iron.

12-inch rifle: In 1864 the Fort Pitt foundry bored 3 XV-inch Dahlgren shell gun blanks, one was finished using the Atwater design, one with the Parrott design, and one with the Rodman approach. The Rodman solid shot weighed 618 to 619 pounds and the Atwater solid shot 416 to 535 pounds. The weights of the Parrott projectiles are not recorded. In 1867, at Fort Monroe, the guns were tested with charges varying between 35 and 55 pounds until the guns failed.