2.3gr of Hodgon Clays with a heavy crimp at the leading edge of the Hornady 148gr HBWC bullet is about the cleanest I get out of 2.5" 686-4 and 3" 66-2.

The heavier crimp is essential to a cleaner burn of this fast powder.

You can start at 2.1gr of Clays

Try Winchester SP primers for this load.

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