Shaving lead using rcbs dies,

[44man]

What you guys are overlooking is that he is using a Dillon 550, and the expanding die from your normal RCBS (or whatever) die set, or a Lyman M die is not used! You're pretty much stuck using the Dillon powder funnel to expand your brass. Sorry, but I get annoyed reading responses from people who obviously didn't bother to read the entire post before they started typing.

To the OP: IIRC, one of the machinists on this forum has made custom-sized powder funnels for Dillon presses before, though I can't recall who it was. That's probably your best option, short of expanding your brass on a single stage press before loading it on your Dillon.

I was not referring to the expander or flaring of the case, just the seat die and if it is too tight for cast and is closing the flare on entry.

[Matt_G]

You did chamfer the mouths of the cases, right?

[mpmarty]

With the Dillon 550 it's all in setting the powder measure down far enough to properly bell the case mouth.

[uscra112]

Another reason I don't ever want a progressive loader in my life. . . . . .

[popper]

I guess he figured it out. Probably needed to move the seater die out and the plug down so he didn't seat and crimp in the same step.

[birddog]

You stated that you had adjusted case mouth flare to just fit the seating die, next I would suggest a seperate taper crimp as dillon uses or the redding taper crimp die.

[918v]

.40 dies are designed for .399"-.400" jacketed bullets. Introducing .401"+ into the mix will cause internal issues. If the OP flared more, the seater die will simply unflair it while seating. If the bullet is started crooked, it will seat crooked and lead will be shaved off. Seating and crimping at the same time works, but only if the seater die bore is big enough to allow it with an oversized bullet, otherwise it will shave.