Ken,
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<br>I hear you loud and clear on this. It jibes perfectly with my experience over almost forty years of loading. In fact, right now I am looking forward to taking advantage of just this principle in a 270 rifle I am having rechambered to 270 Wby. It already gives me almost 3200 fps with a certain charge of H450 from a 24" bbl.
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<br>After the rechambering the same charge will obviously give me less velocity, because the case capacity will be increased. Increasing the charge will bring the velocity back up, even though the pressure may be lower. Going to an even slower powder, say Re 22, Re 25 or 7828, one should be able to get higher velocities still, without primer pockets expanding, etc.
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<br>The fly in this ointment, of course, is that the increased head area will increase the bolt thrust or force the locking lugs must bear.
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<br>Ted
