This model was redesigned by Richard S. Lawrence and William Jones based on a model submitted by Christian Sharps. The change made by the former without consultation with Sharps is part of what led to him leaving the company that bore his name. Estimates vary for how many Model 1851 sporting rifles were manufactured between 1852 and 1855 by Robbins & Lawrence in Windsor, Vermont, for Sharps Rifle Manufacturing Co. Noted Sharps researcher Frank Sellers estimated 193 manufactured within the 1-2050 range in "Sharps Firearms" and only 53 in this basic configuration (caliber/barrel shape/no engraving). Sellers also notes that nearly half of the sporting rifles had double set triggers and half had single triggers like this one, further increasing the rarity of this configuration. It has a blade front sight, "squirrel ear" rear sight, "ROBBINS/& LAWRENCE" on top of the barrel at the breech section, "EDWARD MAYNARD/PATENTEE/1845" on the primer door, "C. SHARPS PATENT/1848" followed by the serial number on the upper tang, brass patch box and buttplate, sling ring mounted on the lower tang, and smooth stock and forearm with grey enamel covered pewter nose cap. This was the last model before the Sharps rifles and carbines began taking their classic shape and is an important early variation. This model was also the first Sharps used by the U.S. military.

Very good, retains 75% of the thinned refinished brown finish on the barrel, silvered case colors, attractively aged patina on the brass with a light speckling of brown patina on the action. The wood is also very good with some minor dings and scratches scattered throughout, some minor chipping and a crack in the darkened forearm, and some chipping near the toe. Mechanically fine.