Barrelnut
Well-Known Member
Good point. This is particularly true of older Forster seating dies. The cup of the seating stem is thin and can get a hairline crack on the side that results from excessive pressure seating a bullet. It is hard to see and can cause CBTO issues and possibly runout too. You can often feel the crack with your fingernail. You can order an new one from Forster. The newer ones are thicker in the cup area which resolves the issue. Both Forester and Redding seater dies are excellent but the tip of the hat goes to the Redding.If your cbto is also varying then your forster micrometer bullet seating stem is messed up.
Forster stems are extremely fragile.
Get rid of that die and get a redding micrometer seater if that's the case.