20in 6.5 PRC 140 class powders?

[ID-Muley]

Doing some load development for a buddy and it’s a 20in plus can barrel and a short action. I’m going to run some 140 class bullets and lapua brass. What mostly temp stable will give the best velocity? I’ve read a ton and seems like N560 is king with this combo, but also I believe it’s not as temp stable as N565 or H1000. So I’m guessing N565 or H1000 is going to be best. Does one over the other win for this combo? LR or magnum primers? I’m pretty sure both work well? I’be read a ton and hoping there’s some more people that have had similar setups now instead of posts from a few years ago that might not have everybody chimed in.

Thanks

 

[streamerfish]

If your going for max temp stability H1000 and 565 your on track. I would throw RL23 into the ring as well.