I think of the powder's you mention, Hybrid 100v I've never heard of. RL-22 just might be a bit slow and 4064 I believe to fast burning. 4831 with that heavy bullet I'd think would work well if the rifle likes it. Even though I think RL22 might be a bit slow, I'd still try it and I'd try RL19 also. I learned that choosing the powder depended on the size of the case and the weight of the bullet. it's always worked for me and I see no reason to change. A large case and a heavy for cal bullet seems to do best with slower powders. I learned to look in the manual for the powder's that gave the best velocity with the bullet I was using and for whatever reason, it has always worked out well for me. So I get out my Hornady manual and to me it looks like most of the powders you mentioned would be fine. I'd check on RL22 for no other reason than even though it get's the best velocity, it takes more powder to do it. I check in the case to see where the powder come's up to. I think I've read that ideally the powder should fill up to , I think it was, 85% of the volume. Full I consider to the intersection of the neck and shoulder. With the 150gr bullet it might be a bit less than that. I say that because i don't care for any powder compression at all. if your compressing powder, the powder for me is to slow. I seat bullet's to the base of the neck and that 150gr bullet might be to long to do that with. I'd simply load out as far as I could and live with what's left. That 150gr bullet should be a good one in a 270! Something I found out with a 7mm mag years ago that I couldn't load the bullet out far enough, the lands stopped me. It was a Sako L69 and plenty long action so I loaded up a dummy with a 160gr Speer as long as I could and in that case loaded to the base of the neck. Fit in the magazine but not the chamber. Had a gun smith take out the lands and make that round fit just off the lands and it shot great to say the least! The only 270 I ever had I used the 140gr Hornady interloc in and it did load even with the base of the neck and still fit the magsazine. But it was a Harrington-Richardson built on a Sako L69 action. If you try this make sure the dummy will fit in the magazine first. Oh, and be ready to increase the powder a bit more also. I went from 67.0grs N205 to 69.0grs N205.
This is interesting and I’m watching! Just getting into reloading under the guidance of a mentor who did it for years when he competed. I do have Accurate 2700 if you’re interested to know how that powder preforms. They say “like 4831” like Toyota is like Ford I don’t know, we’ll see.
Can you give me an idea of powder weight for your load? Near max or mild load?
