I have already checked the web site but can't find any data for the 425 gr . I have emailed them and waiting for a reply.Mikey said:bea175: Ii have used the Beartooth Bullets in my 444s and love them for their accuracy and performance. I have found the Beartooth loading data to be just excellent. My suggestion is to go to their website for loading data for that bullet. If their data for the 45-70 is anything like their data for the 444 (powder selection and charge, oal, velocity and group size)they are providing you with a wealth of loading information available for your immediate use. I would check their data to see how that bullet performs with 4198. HTH. Mikey.