I assume you mean an H&R Premier revolver. Lots of luck, as it is nearly impossible to find people to work on those old guns unless they do it as a hobby. It sounds like the trigger spring is broken (a common problem); springs are available from Wolff's (www.gunsprings.com
) but will require fitting.
Work on those revolvers is tedious and difficult; just fitting that spring could take a couple of hours, counting dis- and re-assembly of the gun. And that, at reasonable rates, would be more than the gun is worth.