There is a lack of a good data base for H&R serial numbers. The seven shot early model of the Hunter revolver dates from around 1900.
Winchester Magnum rim fire
H&R- Harrington & Richardson.
H&R- Harrington & Richardson.
Cornell Publications might have a book with that information.
200 USD
H&R does not have a patent dating from 1850 - either you have the wrong company or the date was misread??????????????
H&R makes a 22lr 9 shot revolver, Model 904
25-125
Best left to a gunsmith.
Winchester magnum rimfire
50-125