Ya I just went with a SAAMI spec reamer, I dont think I should have any issues, we will see once the 156's come out. Those are the only ones I would be concerned about being longer than 3.340" seated close to the lands.
Ya this rifle should be fun, went with Burris ruger to weaver bases and Burris signature series ZEE rings, and vortex 4-16 PST optic. Awesome thing with the rings is I can get however much cant I need to get the most out of the scope. What kinda velocities should I expect with 147's? I have heard H1000, Reloder 26, Retumbo, and Reloder 33 will get best velocities
The 264WM will give you a LOT of reach without needing a large range of adjustment in your scope. I expect the Burris rings to allow you to set up your basic zero, while leaving the scope adjustment on, or near, mechanical center. Should be a very user-friendly setup.
I worked with Retumbo and RL33 in my 264WM. RL33 acted like it wanted more start pressure. I couldn't get any kind of consistent velocity with it and 140's in my rifle. It may work better with the 147's/156's and 7.5 twist in your rifle, though RL33 has a reputation for being VERY temp sensitive, more so than most other Alliant powders (and I am one who prefers Alliant powders). If it works for you, I wouldn't be surprised to see the accuracy node show up around 3200, or better.
IMO, Retumbo is the best choice for the 264WM. It is an Extreme powder, has the right amount of bulk, and produces both good velocity and accuracy. With 140's, the accuracy node appears around 3150 from a 26" barrel, at mild pressure levels (can't safely reach the next higher node). QL predicts an accuracy node with Retumbo and 147's @ 3100ish.
If you can obtain N570 (and are willing to pay up for it), I have heard it betters both Retumbo and RL33. I have wanted to try it, but have never been able to get my hands on it.
My experience with RL26 in other chamberings leads me to believe it is not a good choice in 264WM. RL26 is a very dense powder and the 264WM has more case capacity than it can use efficiently, even with slower, bulkier powders. I suspect that RL26 would yield poor load densities and pressure out early in the Win Mag case.
I don't personally have any experience with H1000, but its bulk and burn rate could well make it a good fit in the 264. Its reputation for temp stability wouldn't hurt, either.
