leadchucker
Member
When adjusted per the video in post #15, that is, without the black plastic tab hitting the top of the slot, the Auto Drum depends solely on spring pressure to flare pistol case mouths. At least, that's how mine works. Wouldn't different strength springs give you different amounts of flare?
I have to guess that Lee intended for the measure and die to be adjusted so that the black plastic tab does not hit the top of the slot. Adjusting it so it does will increase the amount of flare, but it also increases the likelihood of breaking something.
It requires about 55 pounds of pressure to compress the stock spring. It takes every bit of that spring pressure to overcome the measure's internal friction when the drum is tightened so it doesn't leak. (I know that because I tried fabricating weaker springs. They didn't work.) That stock spring pressure is waaay too much spring pressure (and flaring pressure) for some cases like 380acp. If you raise the powder through die to reduce the amount of pressure (and the amount of flare,) the measure won't fully cycle.
That spring pressure and that plastic tab are the two problems that make the Auto Drum unacceptable to me.