A few years back, I made a pistol gripped percussion Hawken rifle for a friend, and he wanted a peep sight with it. Once I had a load and the sights regulated for the iron sights on the barrel, it was a simple matter to adjust the peep sight so that looking through the peep, I could see the rear and front sights too. In truth, the peep clarified the rear sight making it crystal sharp, and accuracy was better using all three sights. Although I didn't check it out, I think I could have removed the rear sight from the barrel and done just as well without it...certainly would have been less cluttered.