The Pettengill revolver is a 6-shot, muzzleloading double-action-only system designed and patented by C.S. Pettengill in 1856, and improved by Edward Raymond and Charles Robitaille in 1858. In 1859, the Rogers & Spencer company was contracted to put them into production as a .31 caliber pocket model and a .34 caliber Navy model. Shortly after the outbreak of the Civil War, Amos Rogers took a couple of the .34 Navy models to Washington DC to look for a military contract. The Secretary of War was impressed by the double action system, and ordered a contract for 5,000 of the revolvers. The contract was signed on January 10, 1962, and it requires the first thousand guns to be delivered in 90 days, with 1,000 more per month after that.

When the deadline for the first thousand guns came around, Rogers & Spencer only had a single sample ready. What they thought would be a simple process of scaling the gun up from .34 to .44 caliber actually required some re-engineering, and that had taken time. So they sent the sample, which was duly evaluated by Springfield Armory. They deemed it well made, reasonably reliable, and unfit for military service because of the double action only trigger. As a result, the contract with Rogers & Spencer was cancelled. This must have come as quite the shock to the company, as the DAO trigger was the main selling point of the gun - and because they had invested a whole lot of money in tooling and material to fulfill the contract. Fortunately, they were able to make the case to the government that cancelling the contract was unfair and would completely bankrupt them, and a new contract for 2,000 revolvers was issued in June 1862, essentially just to bail out the company.

Ultimately all 2,000 guns were delivered in late 1862, and they were put into service in 1863 to good effect. In fact, a second contract for 10,000 more of the revolvers was issued in April 1863, but never fulfilled because Rogers & Spencer developed a new revolver to replace the Pettengill. After the Civil War the surviving Pettengills were put into storage for a few decades. An initial batch of 196 were sold in 1976 for $1.75 each, and the remaining stock of 525 more were sold as a batch for $143.75 in 1882 (that’s 27.4 cents each).