I’d go further. In virtually every situation, there is zero accuracy advantage to neck-only sizing, and it’s likely neck-only cases will have to have the shoulder bumped every few firings or else sticky extraction will occur.
Every LR BR competitor I know and shoot with bumps the shoulder around .001 to .002. One fellow, who has NBRSA Hall of Fame points, shoulder bumps AND small base sizes his cases before each Nationals. I have experimented with small base sizing as well and haven’t any difference in accuracy at 600 or 1000 yds either. This data point is completely counter to the idea that a neck-only sized case is more accurate because it fits the chamber better.
I think the idea that neck-only sizing is better was propagated by gun writers 40-50+ years ago. The initial ideas were to set the sizer so the shell holder touched the sizer die, seat the bullet to the COAL length without measuring ogive, and reloading was often presented as a way to same money on ammo. All this was mainly for factory hunting rifles with the typical huge chambers.
Of course neck-only sizing and seating with the ogive would give better accuracy, but there was often that sticky case issue after three firings. Somewhere along they somebody discovered that you could get at least as good if accuracy by bumping the shoulder .001 to .002, and that pretty much resolved the sticky case issue.
Very interesting history lesson. Every once in a while I enjoy someone sharing these great nuggets of knowledge. Thanks...









