So I have been reading about the donut that forms at the case neck/shoulder junction and that its best to not seat the bearing surface of the bullet past the neck/shoulder junction so that if there was a donut, the bullet and neck tension wouldn't be affected by it. Most of the stuff I read, says that the donut happens with fireforming cartridges from other parent cartridges or with forming wildcat cartridges. My question is, does anyone know if a basic 308 case is prone to the donut forming? I would like to keep my bullets bearing surface above this area in the case, but sometimes its impossible when utilizing the 175-178 bullets because of magazine restrictions and/or freebore distance. My cases are on their 4th firing and I cannot see or feel a donut but I know that is not actually measuring it to see if one is there. Do bushing dies that partially size the neck help? It seems to make sense that they would, since it wouldn't size the area where a donut would be.