https://thegreatmodel8.net/

This 81 of mine has two holes in the tang, did someone tap it for a tang sight other than the type that goes in the forward hole.

Looks like that was the reason for the two new holes.It wasn`t done at the factory. They appear to be straight and would give you another option for mounting a sight.Might be able to find something that would go for a little less than the sights made for the 8/81`s. If you decide to go that route just be sure the holes in the sight you find measured center to center are the same as the holes in the tang.
Joe

Yepper, that`s what i was figuring too, crazy thing is a couple months back i gave a Lyman peep that would of fit it perfect to a pard in WY.
Oh well that`s the way it goes.

Sure looks like someone adapted a more recent flat base style tang sight to the gun. I can see how one might do that considering the cost of the vintage single hole units made for these rifles. Now that the deed has been done it gives you some options. Not really a bad deal at all. I have tang sights on all but the scoped 8/81's I have. They greatly imporove my shooting with these rifles.