I have been shooting the 50AK for some time now. I've tried several powders.I had good luck with IMR4198,and now using H322.I now have information of people using benchmark powder with a 525 gas check bullet and getting,2000fps. And that is something else,but I have check it out and called serveral people and have the grains to start with. I will use this information and will up data if it works out.If so I think the 50AK will be the round for anything on this earth at a middle range.