David, many thanks for your response; the N. J. is stamped into the rear of the barrel (in the area of the proof mark) and repeated on the left side of the stock where the lock screw heards are located. It denotes the rifle was made for/sold to the State of New Jersery rather than the Federal Government. The Colt "veified proof" is the problem as it is a combination of the letters "V" and "P", with the "P" not under the "V" but incorporated into the right arm of the "V". The normal proof mark is a "V" over "P" over "eagle head". Is definitly civil war issue COLT SPECIAL MODEL 1861 rifled musket, with lock and barrel date of 1862. Have been told that the form of proof mark on the musket denoted "second quality" but have not been able to confirm that with any reference book, but have seen it with many other N.J. surcharged muskets. Musket has family history of having been inssued to Joseph Swickerath of 23rd. N. J. Infantry and purchased by him at the time of his discharge as evidenced by a printed form acompanying his discharge papers. The markings on the lock plate are all the standard Colt markings. Am trying to attach photos. Thanks. Mikd