Interesting. I anneal after every firing, I was using a bushing that gave me about .002 neck tension without the exapander ball. Come to think of it though, I dont usually lube the case necks, just the body of the case. Ill have to see what that might do for me.
Lube on the neck for a FL bushing die is really important. You might find that solves the problem. Good luck.
I usually mandrel after FL sizing and dont use the ball as well, but in trying to eliminate the doughnut issue, Ive been trying a lot of other things lately.
I'll bet you a nickel that a good neck-lube will solve that problem. Before FL sizing, I line up my brass standing on a cookie sheet, and spray down at a 45-degree angle in all four directions with Hornady One-Shot Case Lube Spray. That has the added benefit of also getting inside the neck to make mandrel'ing much easier as well.
^^^^^ This^^^^^. Use the bushing F/L sizer for the case body (W/O the bushing installed) and then use a Lee Collet N/O sizing die. This makes very accurate ammo with very low runout.
Great ... BTW ... the mandrel set from 21st Century is awesome, and allowed me to test and use the very best mandrel for the neck tension that gave me the best accuracy. Kind of expensive ... but worth it IMHO.
Projectiles vary slightly ... what I've found works is to accurately measure the diameter of the projectile I'm using, and employ the mandrel that is 2/1000's smaller that that size. Never needed a pin-gauge, but I suppose it would never hurt to use one. I started with the caliber-specific LE Wilson Mandrel die, but quickly realized that "One size doesn't fit all", and got the 21st Century set, which works much better (for me at least). Bottom line ... the mandrel I use is more about the projectile, than the case. I size the neck "down" with a bushing die, and then "out" with the right mandrel that's 2/1000's smaller than the projectile I'm using. Fun stuff ... keeps my brain busy.
