These were most probably Robbins and Lawrence model 1841 Contract rifles according to my copy of "Echos of Glory", 2,000 of these were stored at Baton Rouge Arsenal at the outbreak of the war, 15,000 being manufactured overall. The U.S. Model 1841 "Mississippi" rifle was issued as a .54 cal but many were rerifled to .58 cal after 1855.

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