What presses and dies are you using and general equipment recommendations.

[Klem]

The locating buttons just keep the brass from falling out. You can run the press without them if you're not too rough.

ETA: To clarify, the button keeps the brass aligned in the shell at the die station once you're running full speed. There are breaks in the ram face so brass can be removed or inserted, the buttons keep the brass from coming out. Runout in rifle brass on a Dillon 550 or 650 is normally caused by tightening the die lock rings without a piece of brass in each station.

Yes, I am aware of the obvious function of the retaining pins, which is to retain the case while it spins at speed.

What I am referring to is the other role of the retaining pin, which is to index the case at the edge of the bottom plate. I only have one Dillon plate which is 9mm. No doubt the diameters of plates vary depending on calibre. Given the holes the retaining pins sit in are fixed their button diameters will be different diameters to account for the different diameter bottom plates. This is how Dillon solves manufacturer-induced run out in a generic machine.

Your practise of raising the ram and screwing in the die's locking nut with a case in it might also help.

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