I'am new and did'nt have any thing to do today so I went through a box of reloading dies I got years ago and found a set marked p.p. swage. I figured they are primer pocket swage dies as the male portion fits a empty case pocket and there are two of them. One large primer and one small primer. The number on top the die is 80 its an rcbs set and their web site does't have anything about this item. Do any of yall know what these are goog for?

They are used to swage the crimp out of military brass after you deprime them. Otherwise you would not be able to seat a new primer.