"if it uses more powder, at a lesser pressure, to out perform the 220 Swift how is it on barrel life when compared to a Swift?"
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<br>If you'll read my earlier post -- really study it and absorb all its points -- you'll see the answer right there. I listed those five principles of interior ballistics separately in my post, but they're integral to a single system and to each other. Like someone said about truth, they're indivisible.
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<br>When the .220 Howell is loaded to lower pressures than the Swift factory load (and typical Swift handloads), those lower pressures guarantee slower throat erosion. The substantially larger case accommodates larger charges, which produce more propelling gas, which in turn produces higher velocities.
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<br>If I loaded the .220 Howell to the same pressures as the Swift, throat erosion in the .220 Howell would occur as rapidly as it does in the Swift. (And the muzzle velocity would of course be even greater than either the Swift's or my "economy cruise" velocities.)
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<br>My larger case is enough larger to let me increase my powder charge (compared with the Swift) without going to the limit that my larger case can accommodate.
