FWIW I've shot one test series with 200 Ptn & RL26. WW brass & 215s @ 3.580"OAL in a 24" barrel. Speeds measured at 10' not corrected to MV, so add... 25-30fps. It was 75* that day with a good breeze. 4-shot groups. No bolt lift noted, no other sign of pressure.
67-2759
68-2792-best group that day at 1 1/4"
69-2840
69.5-2845
70-2876
Speer #15 has data for newer powders. They stopped at 68.9 of RL26 in Federal brass with a 215 @ 2780fps.
