When I saw your other thread and your use of H-1000 I almost commented then. I think H-1000 isn't slow enough. RL-33 and perhaps US 869 would be better choices.
I used RL-33 in a Bartlein 5R, 28'' , 1 in 7.5 twist, 6mm-284. Bullet was the 105 Berger hybrid, Lapua brass and Fed 210 match primer.
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The bullet's seating depth was set so loaded ammo would fit and feed from a Wyatt's mag box in a SA Remington. Jump to lands .065"
As a reference: 58 gr of Retumbo was most accurate with velocity of 3307 fps.
RL-33 shows on the scene:
Using same seating depth an components I worked up loads.
62.5 gr 3376
63 gr 3414
63.5 gr 3453
64 gr 3484 most accurate load requires a drop tube to get the powder to fit
64.5 gr some pressure signs
I used the 64 gr load to shoot a coues wt at 525 yds four years ago using the 105 Berger. That buck wasn't huge, the bullet killed just fine.
WARNING. Another guy on LRH tried to work up to 64 and got pressure far earlier than my rifle. When RL-33 was used the barrel had 928 rounds through it and I was jumping the bullet.
I was able to start with RL-33 with some pretty low charge weights. As you know there is still little load data on this powder. I have no idea on where you should start with such a heavy bullet. Hope this helps some.
