Sticking a cotton bud down the top of the die and working it around the neck area should show if there are any rough areas.
Type: Posts; User: Cigar
Sticking a cotton bud down the top of the die and working it around the neck area should show if there are any rough areas.
Zooming in on the photo it looks like it must be imperfections in the die, definitely looks like its burrs or something near the base of the neck section scraping brass down the neck