We have several Marlin big bore .444 and .458 shooters around here who have been turned on to Accurate 2015 for the best powder going. There are reports this powder gives sub minute of angle groups and very high velocities with excellent pressure ratios. None of us have any experience using this powder. If you can help us out with your expertise, we would appreciate it. We are getting ready to go lion and bear hunting in New Mexico. We will be shooting 350 hard cast slugs along with Remington heavy 400 grainers in guide guns and in the longer barrel Ninety Fives.