I can't say about a Ruger #1, but I bought a new Winchester 1885 highwall several years back and it didn't come with irons which I found annoying since an 1885 just screams opens sights especially on an octagon barrel. Anyway I took it to a gunsmith and he put it in his mill and cut the dovetails. Brownells use to sell and maybe they still do a jig for cutting your own dovetail slot with just a file (work!). Anyway back to my highwall the octagon barrel had a good taper to it and not thinking I bought some nice vintage looking sights, but the front sight wasn't near tall enough. I eventually found and had to put on a tall globe sight for it to work. I like globe sights with inserts, but this one is so tall it looks like an anti-aircraft sight. There is a formula for determining sight height so if you think you'll need it I will post it or you can google it. Hope that helps.