This J P Clabrough(?) shotgun appears to be about mid-level in quality since there's some engraving.
Your statement that it "locks up tight" is a positive point in the guns favor.
As far as 'shootability" goes the first thing that must be examined is the condition inside of the barrels. Post some pictures here and you will be advised as to how to proceed.
Jim

The 2nd Amendment IS an unalienable right.