270 wsm+p powder options

[The Fish Box]

I am trying to figure out if I should try another powder or call what I got good enough. With 150 grain accubond long range.

Rl26 with 67 grains and some space left in the case went 3200 ish before pressure

N570 maxed out the case capacity at 70 grains at 3100 ish with no real pressure.

Is n568 going to be too slow still or will I be able to get some more in the case for a boost in velocity? Not a huge fan of RL26 seeing as it went from no pressure to a primer popping on me in moderate temps so I would like to get away from it.

 

[B23]

So you're looking for something with similar performance/velocities as RL26 but more temp stable, yes? Maybe give N565 a try or H4831sc. N570 is such a big chunky powder I've found using a longggggg drop tube funnel helps get a fair bit more in the case.

Also, I think if you are going from "no pressure" to popping or piercing a primer with just a moderate temp change your load is already beyond what it should be.

Another possibility, if you're seating your bullets close to touching, and, you're load is at or near redline you should be measuring OAL base to ogive on every loaded round because you could have had one get away from you on seating depth and when you go from close to touching to actually touching or slight jam it will spike the start pressure. Some years ago I had this happen with my 6.5-06AI. I was running right on the edge with 140 Berger's and they were shooting crazy good just a couple thou off touching and I got sloppy and lazy letting a couple slip through that were seated a little long and pierced two primers back to back. I had to quit shooting and go home because it got a tiny piece of crud in the firing pin hole and jammed things up. Got home and started evaluating what hell was going on and when I measured OAL base to ogive on some that were still in the box I'd loaded they were indeed long so they were actually slightly jammed and touching not a few thou off like the others. When you run on the edge you have to make sure everything stays consistent because there's no longer much if any room for error.

 

[The Fish Box]

I don’t doubt that I was at the upper end on pressure but not any more so than other rifles I have used looking for the same pressure signs.

But I hadn’t thought about the pressure spike from a loaded round being long, seeing as I had issues with coal growing slightly in that cartridge due to it being compressed that could have been part of the problem.

Anyhow in the 270wsm+p I am trying to also get slightly better case fill, the rl26 isn’t filling the case so if I could kill two birds with one stone (full case, get away from RL26) I will take it and hopefully maintain the velocity of RL26.

I also use a 30 ish inch drop tube ( old aluminum arrow).

 

[B23]

I'd give N565 a try first followed by H4831SC. Both of those will get you the case fill you're looking for and should be close to the same velocity.