That is a first or second year of production 1895, the big screws in the studless forend cap and the BO prefix are unique to those two years, I believe they are 71-72 but could be off a year or two. The barrel has been cut and the long mag added, the stock has also been cut for the pad, would have had a curved butt from the factory. It probably also has a different rifling pattern, coarser than Microgroove but not as deep as the later Ballard cut barrels. That rifling pattern is unique to the first two years of production.
The straight stock 1895 was made until 1980, they changed to pistol grip then and didn't make a straight grip again until the Guide gun came out in the 90's. The non crossbolt safety pistol grip guns are the rarest, they were only made from 80-83.