Polishing Die Seating Plunger

[Old Timer]

My seating plunger is scratching my VLD's. small scratch all the way arnd the bullet. What would be the best way to polish it? Can I tape up the threads and stick it in the tumbler? Or use a bore mop with some lapping cmpd?

Old Timer

 

[jlcprec]

It may be that your seater stem doesn't have the same taper as the VLD bullet, so it is contacting the bullet on the edge of the seater stem. With a lot of neck tension, this could leave a ring around the bullet.