Got a custom 300 ultra that I am getting ready to reload for. I was curious what would be a better powder or what is preferred by you ultra shooters, retumbo or H1000? I currently have a couple pounds of H1000 and have no problem going out and getting retumbo if that would be a better choice. Was going to load for 210 bergers or 200 accubonds whichever shoots better. I was just looking for a little feedback before I spend everyday looking for the combo that the rifle likes. Any info to help me cut down on the "perfect combo" phase is greatly appreciated. Waiting to get the rifle bedded, so I got a little time. Will post pics and specs when it is complete. Thanks in advance!!