Thats a good question,of which only a qualified gunsmith can answer.I can say that the new heat treatment on the Springfield model of 1903 began at serial number 800,000.So yours has that in its favor.Your serial number indicates that it was made in the year 1918.So it could have seen service in World War I.Have it checked by a qualified gunsmith and then you can sleep easy as to if it is safe to shoot.
Your model 1898 krag was made by springfield armory in 1899.
I can say that your rifle will range in price from 300-2,750 dollars depending on condition,markings on the stock and barrel,and if all parts match or not.
Your springfield armory model 1903 springfield rifle was made in 1932.
Model 1911a1
Serial # N5102889 Made
about 1914
your springfield 1911 was made in 1914
your springfield model 1903 was made in 1920.
Your springfield model 1898 was produced in 1899.
your springfield model 1903 was produced in 1923.
With the serial number provided,your springfield model 1898 krag,was made in the year 1899.
No published sn data. You will have to call Springfield Armory