To make it really easy, use the parts list / parts number that is in your Owner's Manual. Or go to the Dillon website, and down load the Manual to your computer (uses Adobe PDF file free software) and you will be an expert. I have received 20+ pieces and ordered 2 small parts kits (about $10 each) since 1983. The small parts kit was the only thing I've paid for.

Over the years, I added auto prime, auto powder, and auto eject to my original Dillon 450. I also bought a new upgraded powder measure, when the original D 450 measure cracked it's main casting. The failed powder measure was replaced for free. The purchased powder measure went on my used Dillon 550.

Dillon costs a little more, but the service, tech support, and replacement warranty are priceless.

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S&WHF 366