I'm perplexed! I began loading for my .454 a week or so ago while using the data from my Lyman 49th edition manual. What I discovered was that minimum loads of 2400 and IMR-4227 were very much near compressed loads. Mid range loads had the powder (as far as I can measure) right up against the back of the seated bullets. H-110 seemed nearly the same too. I could never load a max load for any of these powders as they'd be jammed up against the bullet or nearly overflow the case. I've noted this problem with a few other calibers as well, including the .357 mag and .30 carbine, especially when loading IMR-4227 and 2400.
Back to the .454 Casull; I've recently looked up some loading data in the Hornady manual and the loads listed there are even higher than those listed in the Lyman manual. I'd imagine that with some of the loads listed there, the powder will be nearing the top of the cartridge and nearly overflowing. Is this right?
I've calibrated my powder measure and checked it with purchased standardized weights and my powder measure is right on the money. I wonder what is wrong.
Do any of you reloaders actually compress loads that much, even when the manual doesn't state that it's a compressed load? I'm a little scared of doing so but I'd like to try some heavier loads if possible.
Any thoughts are appreciated.