This is a very scarce version of Civil War rifle. This is one of the guns that were marked with the Union Arms Company lockplate. The Union Arms Company (U.A. Co) marked contract US Model 1861 Rifle Muskets have always been somewhat of a conundrum to arms collectors and researchers. The firm was organized by R.H. Gallagher who had acquired the rights to manufacture Marsh Patent breechloading rifles. Another member of the organization was Edward Robinson who would go on to delivery Model 1861 Rifle Muskets under his own contracts later in the war. Gallagher initially received a contract in the summer of 1861 to deliver 25,000 of the Marsh patent guns to the Ordnance Department, but the contract soon canceled and replaced with a contract to produce 20,000 US Model 1861 Rifle Muskets. Additional contracts followed and soon the firm was contracted to supply 60,000 Model 1861s. Since the firm had failed to deliver anything by the fall of that year, terms were renegotiated and in April of 1862 a new arrangement was made, calling for the delivery of the original 25,000 Marsh rifles at a new, lower price and reducing the number of US Model 1861 Rifle Muskets to be produced to 25,000. Like so many of the contractors who intended to build Model 1861s, Gallagher had no intention of making all of the parts, or even most of the parts, in house. Rather he was relying primarily upon contractors for the parts which his firm would then assemble. The first Union Arms Company delivery was of 300 rifle muskets which were all rejected. It is believed these were later sold to the state of New Jersey, as at least one extant example survives that is marked with condemnation "C" marks throughout and is New Jersey surcharged. Whether the initial delivery of poor quality muskets was the reason, or the constant delays and failures to meet the contracted delivery dates, the Union Arms Company contracts were voided and the firm collapsed. It appears that Edward Robinson acquired some of the parts that were on hand when the company failed and used them to produce Model 1861s for his own contracts. Between 1863 and 1865 Robinson would managed to deliver some 30,000 Model 1861 Rifle Muskets out of a total of 90,000 that was contracted to manufacture, with the early guns having the U.A. Co (Union Arms Company) marked locks. This one has the "U.S. and U.A. CO./NEW YORK" maker mark and is deeply stamped on the lockplate. Also on the lockplate are the production date of 1863 and the Union eagle with the "US" below. The action works superbly on all positions. The barrel is full length with the bore being about fine, partly bright with crisp rifling and some scattered oxidation. At the breech of the barrel is the correct inspector marks as well as the matching 1863 production date of the barrel. The left flat of the breech has a block G.E.C inspection mark for George E. Chamberlain. Since the gun bears the "G.E.C" barrel sub-inspection of George E Chamberlin who inspected arms delivered by Robinson, so it appears that this may be a correct Robinson contract M1861 with the rare, early delivery U.A. Co. marked lock. The original rear sight is present with both of the leafs remaining. Both of the original sling swivels are present and accounted for. In the channel underneath the barrel it has a fine original full-length ramrod. The stock has a nice look with light service wear that you like to see. When you look at the flat of the stock opposite of the lockplate you can see the remnants of the inspector cartouche for Orville W Ainsworth, "OWA". This is a great looking Civil War rifle musket by Robinson.