Haven't used them in my 300 ultra, use barnes 168gr. But did work a load up with the Scirocco's in my 270. Took many trips to the range. Found them tempermental to overall length (seating depth). The olgive of the these bullets gave me a very long OL. I had issues feeding them from the magazine with the long length. Feeding one at a time on the bench obviously not a problem but hunting became a problem.