US Navy Ordnance of the 1845/1846 System

Oct 15

Table from John Dahlgren's book "Shells and Shell Guns", pg. 26.

In May of 1845, a board of US Navy Captains recommended a system of ordnance for the navy. Their report called for the Navy to standardize on the 32-Pounder. Whereas ships had previously carried 18-Pounder, 24-Pounder, 32-Pounder, or 42-Pounder main batteries depending on the size of the ship with carronades on spar decks or as the main battery of small ships, in the new system, all would be replaced by 32-Pounders of different weights. What would vary would be the maximum powder charge each model could handle. In addition, small numbers of 8-Inch shell guns on the broadside or even larger 64-Pounders or 10-Inch shell guns as pivots would be used.

The 32-Pounders were intended to be used:
32-Pounder of 27 Hundredweight - aboard the smallest sloops, possibly also as a replacement for carronades
32-Pounder of 32 Hundredweight - aboard intermediate sloops
32-Pounder of 42 Hundredweight - aboard the largest sloops
32-Pounder of 46 Hundredweight - aboard smaller frigates
32-Pounder of 51 Hundredweight - as chase guns aboard heavy frigates and ships of the line
32-Pounder of 57 Hundredweight - as main battery guns aboard heavy frigates and ships of the line.

The larger guns were:
8-Inch Shell Gun of 55cwt - a small number for the spar deck of heavy frigates and ships of the line
8-Inch Shell Gun of 63cwt - a small number for the gun decks of heavy frigates and ships of the line.
8-Inch Shot Gun of 106cwt - as a pivot gun aboard steamers (one survivor)
10-Inch Shell gun of 86cwt - a a pivot gun aboard steamers

Note: the “hundredweight” which this system refers to weighs 112 pounds. It may be abbreviated “cwt”. Therefore the 32-Pounder 57cwt nominally weighs 6,384 pounds (57 x 112 pounds).

The system was largely based on that which had been adopted by the Royal Navy several years before.

Lieutenant John Dahlgren was one of the ordnance officers placed in charge tests of these new 32-Pounders. One of them burst right in front of him in testing with tragic consequences for one of the gunners. The 32-Pounder of 57 Hundredweight, intended for the main batteries of heavy frigates and ships of the line was found inaccurate. The uniform 32-Pounder battery was intended to simplify ammunition supply in action because every gun would be of the same caliber and fire the same projectiles. However, Dahlgren noted that the problem was transferred to the magazine. If a 9-Pound charge was placed in a gun designed for a smaller charge, the result could be catastrophic. Additionally, he found the 8-Inch shell guns to be more accurate than the 32-Pounder of 57cwt and far more destructive against wooden targets.

The deficiencies Dahlgren found in the 1845/1846 system and the manifest superiority of the shell guns caused him to design his own system of naval ordnance. In a sense, the 32-Pounders of the 1840s led directly to Dahlgren's "Soda Bottle" 9-Inch and 11-Inch guns of the 1850s - with which the Navy would fight the Civil War and which would remain the main armament of the US Navy until the dawn of the "New Navy" in the late 1880s. Read more on John Dahlgren’s Heavy Smoothbore for the US Navy.

Thought the 32-Pounders and Shell Guns of the 1840s were obsolescent by the Civil War, they were pressed into service. The US Navy needed the lighter models especially for the many merchant ships purchased for blockade duty or service on the rivers. In fact, by 1864 the Navy was ordering new models of 32-Pounder and 8-Inch shell guns to fill the need for light guns for ships too small or lightly built to carry to big Dahlgrens.

The Confederacy made use of them for want of anything better. Nearly 1,000 older guns, many of them the 1840s models, were captured at Norfolk in April 1861. While many served as smoothbores, the 57 Hundredweight in particular was a candidate for banding and rifling.

This post includes example photos of the 1845/1846 guns. No US Navy 10-Inch from the 1840s is known to exist. (Only 33 were made.)

One 8-Inch of 55cwt still exists in Poughkeepsie, New York which I have not yet visited.

One 64-Pounder (8-Inch solid shot gun) of 106 cwt is preserved in Waukesha, Wisconsin. It's on my list to visit next summer.

If anyone is near either of those two cannons and would like to send photos, I'd be glad to see them!

Sources for this post are:

Dahlgren, John A. B. Shells and Shell Guns. King and Baird, 1856.

Olmstead, Edwin, Stark, Wayne E., Tucker, Spencer C. The Big Guns: Civil War Siege, Seacoast, and Naval Cannon. Museum Restoration Service, 1997.

Tucker, Spencer. Arming the Fleet: U.S. Navy Ordnance in the Muzzle-Loading Era. Naval Institute Press. 1989.