The Starr Carbine was a pre-American Civil War era breechloading carbine designed by Ebenezer Starr in 1858. The Starr was typically issued to cavalry units (due to its length) and was comparable in terms of performance to the Sharps and later "Trapdoor" Springfield rifles.
The Starr Carbine was designed by Ebenezer Starr in 1858. At that time the most promising breechloading design was the Sharps Rifle (originally designed by Christian Sharps in 1848) and hence Starr decided his rifle would be based on that design. The major differences between the two designs were that the Starr was fitted with a longer receiver and the shape of the stock (which resembled that of the legendary Brown Bess musket of British origin).
The Starr was fitted with a .54in (14mm) bore rifled barrel which measured 21in in length. This, along with all other iron fittings, were given blued finish while the butt plate and barrel bands were manufactured from brass. The Starr lacked any form of bayonet lug, meaning that the Starr wouldn't be fitted with a bayonet, while the sights consisted of a single post front sight with adjustable leaf sight at the rear.
In terms of operation the Starr combined the ever reliable percussion lock system (which had been in use since the 1820s) with the more modern falling block action which allowed the Starr to be loaded from the breech. While virtually all breechloading rifles of that era used a similar if not identical system, the Starr's action (in particular the latter) was modified. This meant it could compete with the newer designs, although testing did reveal that the Starr required a tighter seal around the breech to reduce gas leakage.
The Starr Carbine was given a bore of .54in (14mm) to accept a .54in calibre bullet. This bullet was put into a paper cartridge which was filled with blackpowder (as was the norm). What is unusual is that the majority of military rifles of that era used the Minie ball (a bullet specifically designed to deform to engage with rifling) while the Starr used it's own unique bullet. As it turned out, the Starr proved to be as reliable with its individual bullet.
As can be expected the Starr required a percussion cap to be mounted to the nipple (located at the point where the hammer struck) to fire the cartridge. From 1865, following a redesign of the Starr's action system, metallic cartridges were introduced.
The Starr Carbine was submitted for testing at the Washington Armory in 1858 by its designer Ebenezer Starr. The Starr impressed, easily competing with the Sharps Rifle. One point that the testing did raise however was that the Starr required a better seal around the rear of the breech (which would mean it could have outperformed the Sharps carbine), but otherwise the Starr was reliable and accurate. Nonetheless the Starr was adopted that year as the Model 1858 Carbine.From 1861 until 1864 Starr Arms (operating from their factory in New York) produced 20,000 Starrs for the Union forces during the American Civil War. In 1865 the Starr was modified to use metallic cartridges, which prompted the Union to order 3,000 Starr Model 1865s before the conclusion of the Civil War. Impressed with the performance, the United States ordered a further 2,000, although the contracts would dry up as the Springfield Armory introduced their own breechloading rifle that year (the Springfield Model 1865 "Trapdoor") eventually forcing Starr Arms to close in 1867.
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