I'm useing a RCBS FL .300 Weatherby mag die with the expander removed to neck my .340 Weatherby brass down to 30 Cal.Since this is on new brass that is going to be fire formed,Can I use the .300 weatherby bullet seater just to seat my bullets for my fire forming loads?..Then I will take 3 of the fireformed brass down the street to LE.Wilson and have them build my dies.