At the start of the civil War, the army experimented with many different models of field guns as they tried to find the better gun. An early attempt was the James rifles which were rifled from some Model 1841 six pounder field guns. Some early conversions were bored out in the barrel which left the diameter across the lands at the 3.67" original bore. These guns were referred to as 12 pounder rifles. The weight of the projectile used in these guns was about 12 pounds, hence the name 12 pounder rifles. The James Rifles, Type 1 were the first step in the developmental process, these guns had a land diameter of 3.8" and the weight of the projectile was 14 pounds hence this model was called a 14 pounder rifle. It is a conflict to call rifled field guns as a "Pounder" as they are best described in inches, such as the 3" Ordnance Rifle. Most of the James rifles were 3.8" in diameter across the lands. Smoothbore guns are described as a Pounder, such as the six pounder.
The work of General James came to a halt in October, 1862 when a projectile being tested prematurely exploded.
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