You don't say what powder you're using but my Custom Mauser in the Whelen has a 1 in 14 twist as well. Maxload for the Partition IIRC in the Nosler #7 manual is 59.0 gr. of Re15. I worked up to that charge and accuracy was in the 1.25" range. Now the following load that has worked best in my rifle is 60.4 gr. of Re15 and the Barnes 225 gr. TSX which does between .50" to .75" depending on how well I do my part.I've taken three elk with that load at distances from 150 yards to 350 yards. All one shot kills. I like it. Try playing with the seating depth and see if that improves your groups.
Paul B.

Our forefathers did not politely protest the British.They did not vote them out of office, nor did they impeach the king,march on the capitol or ask permission for their rights. ----------------They just shot them.
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