Hello, I was wondering if anyone could help me out.. i wanna get my Great Great grandfathers gun fixed and was curious how old this is... the serial number is 100051 but there’s dates stamped that don’t align with the serial number list on this website (86)

What a neat connection to your GGGF Justin.
The No. 00 was introduced in 1898 and your gun was made the next year.

Most lower grade Smith guns were bought in bulk and sold by hardware and sporting goods stores, or ordered from a catalog, but it is possible that a Research Letter might document your GGGF as the original purchaser, or at least the sales location
https://lcsca.clubexpress.com/content.aspx?page_id=274&club_id=43784

Please look over the "Shotguns" and "FAQs" sections on the Home Page for lots of information
https://lcsca.clubexpress.com/content.aspx?page_id=0&club_id=43784

After the gun has been evaluated by a qualified double gun specialist, you should enjoy using it, with appropriate shells, for many years and then passing it on to your own grandson

Thank you so much!!! He apparently found this in a barn in the 1930’s. Abandoned barn btw. I appreciate it!