by Bmt85 » Sun Aug 30, 2020 9:00 am
Most pistol bullets have thicker jackets, and are usually a harder alloy, so they can tolerate higher velocities and higher spin rates. They do have limits, though. I seem to remember a member on here that could blow up pistol FMJ's because he was running higher charge weights and he had a faster twist rate. I think 1:16. I would think if you're blowing up pistol FMJ's or seeing excessive copper fouling, you're running them too fast. If not, then you should be fine, as long as you are not seeing any pressure signs.
Plated bullets have a much thinner, and softer "coating". Doesn't take much to scrap it off. They are usually listed at a much lower velocity than jacketed bullets. With 45-70 there seems to be 3 different power levels; old school low pressure type loads, modern medium pressure loads, and stout loads that should only be shot in certain firearms. The plated bullets I have seen are rated around for low pressure (lower speeds and spin rate). Now, the plated .458 bullets should work for the 450B, because they are heavier then what is typically ran in the 450B, so they will run at lower velocities. Plus, the 450B usually has a slower twist rate. Should be able to size them down and run at middle to high end of loads for 450B, and they should still hold together, while still being able to cycle the action. As long as you are using the right powder.
I wouldn't think acceleration (initial acceleration of the projectile when fired) would be an issue for us, unless maybe you're trying to run a plated pistol bullet at 60,000 psi. It would be an experiment all it's own, because you have other factors at play.