Never heard of it?...hmm. When the 284 Win came out in 1963 guys like Bob Hutton went nuts necking the case up and down. The 6mm-284 became one of the favorites early on, then in recent years the 6.5-284 became popular. I have burned out a few barrels in 6mm-284.
Quite a few years ago I discovered that Retumbo worked okay with the 115s. DTACs but nothing that accurate. I blame the bullet not the powder. I switched to the 107 Sierra then to the 105 Berger hybrid when they came out. It was a year or so later I burned out the 30" #7 profile 1 in 7.5 twist bartlein at 1100 rounds so I retired the barrel. If there is a lesson to learn, don't try too many bullet/powder combinations. If you find one that works, stick with it.
When I tried the 115 DTACs it was so long ago that RL-33 was available. Today if I were going to work with the 115s I would try RL-33, which is slower than Retumbo. I found that the mid range load for Retumbo works as a good starting point for RL-33.
I am about to make another 6-284. This time I will use 108 hybrid hunters and RL-33.
H4831SC, and IMO that Berger data stops short of max. I went up to 46.0gn in a slightly smaller case and got 3199FPS from a 30" barrel. RL26 went to 3365 FPS but was no were near as good of groups at any charge. VV565 had accuracy at 3228FPS, but max was 3300. All with 108s, and 115s wouldn't have been much deeper to seat, no more than bringing 6-284 down to 243 AI case capacity.
H1000 should do it's typical job of great precision at about 100FPS less than Retumbo if the accuracy isn't there when you try it.