I decided to try just neck sizing some brass to reload it. I keep reading that it'll make my brass last longer and maybe improve accuracy.
For starters, the rifle in question seems to have good chamber tolerances - fired brass is easy to drop back into the chamber, and takes almost no force to remove. Once I neck sized it, the fired brass slipped right back out with no more force than gravity provides.
But I don't have a separate neck-sizing die. One of my loading manuals says just lower the full-length sizing die 'till it hits the shell holder, back it off one full turn, and you're good to go.
The result is that only a little more than half of the neck gets sized. It looks like the case has a second, smaller shoulder on the neck. I lowered the die a bit further, but the point was not to size the shoulder, so I stopped short of getting the whole neck.
Here's the upshot and the question: The neck on the case is about .3 inches long. I've adjusted my die to leave about .06 inches unsized above the shoulder. Am I good to go, or do I need to go back and do it again so the neck is sized all the way to the shoulder?