Re: Help me cure case neck runout.
If you have thick/thin necks then you will always have a perceived runout problem because everything is wobbling on the indicator...cure that by taking the thick side of the neck off with a turning tool. Note I said take the thick side off, there's no need to even touch the thin side, you'll just feather into it. This will dramatically improve the runout reading. And, if you think about it, you can't possibly have concentric ammo if your bullet is held off center in the neck by a neck wall that is thicker on one side than the other. Turning of course, would be on fireformed brass, and it's a one time deal.
Others have mentioned the floating carbide expander ball, that is my system with Redding FL dies.
Also, my system involves first FL sizing with a Redding die that has no expander ball/decapping stem installed.
To expand the necks I use a seperate sizer die with the floating carbide expander ball installed, and I push the neck up over the expander, instead of pulling it down over. In my experience this makes a huge difference.
When seating my bullets in a Redding comp seater, I'll partially seat the bullet, then turn the case 90 degrees, seat a bit more, turn the case 90 degrees again, then finish the seating stroke. This gentle approach does a better job of seating a bullet straight rather than just cramming it in with one stroke.
It's also my belief that properly annealed brass allows the tooling to do it's job better and more consistantly, which lends to less runout. I anneal after at least every other firing, and usually after every firing.
My TIR gauge runs the loaded round on roller bearings supporting the neck and the "pressure ring", and I usually indicate halfway between the bullet tip and the ogive, where TIR would show up distinctly....I can usually maintain .001" runout or less using this system with match grade bullets.
Of course YMMV.......
