Just bought a 1898 sporterized rifle this weekend at an estate auction. It has a weaver scope 4x, 1901 rear sight good barrel. Last night I thought it may be illegal because I couldn't find the serial numbers. At midnight I thought it won't hurt to take apart to look for any numbers. Under the scope mount I found the numbers.  Two digits are messed up from the drill holes but I believe I can see enough to make out 417881. I was lucky enough to also win the bid on 60 rounds of Remington 30-40.