It depends what you are looking for. What makes a good blue job is the metal prep and polishing. A rust blue is not hard to do yourself but is time consuming. Let me repeat. Your metal prep and polishing before you blue is much more important than the bluing process itself. If you don't know what you are doing you will just mess things up. If you opt to have a pro do it look at some of his work. Rounded edges and ground out stampings or barrels that wave at you in the sunlight are big red flags.
Brownell's oxpho blue works well as a touch up but is difficult to do a whole blue job with. If the rifle is in good enough shape with small wear spots in the bluing it is worth a try. If the Oxpho-Blue doesn't do a good enough job you are only out a bit of time and a few bucks.
Good luck with your project.
