Varminterror, how hot of a load is your 44mag ammo? Close to the .454?
Nowhere close to 454c, certainly not close to full 65kpsi specified Casull loads.
A guy has to ignore the many watered down factory loads on the market like the Winchester Super-X or Federal Fusion which are in the 1,000ft.lb. ballpark, and barely more than Tier 3 45colt loads. Many manufactures are only loading to 50,000psi, or what I suspect is even less in some loads. These are really the only loads where a .44mag can push past a .454c, and for a factory ammo shooter, that might be a valid consideration - pretty easy to win a race when the competition never shifts out of first gear. But when a guy looks at the Swift 300grn load pushing up over 1700fps, or the Grizzly, Buffalo Bore, and Hornady loadings which are full 65kpsi, the .44mag gets left in the dust.
You won't find this data in any manual. These charges exceed published data and are provided for informational purposes only, not as recommendations - proceed at your own risk. By seating to the second cannelure in the 300grn XTP, I get less pressure signs with 22grn H110/W296 than with the published max's of 19.9grn. It's a mild pressure load, respectively, but it pushes the 300 XTP over 1300fps. I have pushed on this bullet until I get pressure signs, which puts me up over 1400fps, but it's a very mean load.
Alternatively, 1,400fps with the 454c is a starting load for the 300 XTP, and I run mine over 32.0grn H110/W296 which yields a touch over 1650fps in my 7.5" SRH's, a touch under 1600 in my Toklats. This is pretty standard fare stuff, I have hot-rodded the .454c in the past, but usually I just end up with stuck cases and jumped crimps, and not much gain in velocity. Getting the 300xtp over 1700 sounds cool, but that 50fps doesn't buy me anything. Jumping from 1300fps in the 44 to 1650fps in the 454 DOES gain me something.
There's a big gap in pressure between the two, which I don't care to close without a carpenter steel cylinder, and the case capacity gap will always leave the 44mag a long ways behind the Casull, even if a guy chose to load to similar pressures.