Lots of competitive rifle shooters soft seat bullets long so they are set back a few thousandths when chambered. Cutting the powder charge 1% fair the well compensates for pressure increase, but I never did because I think it's enough to matter. Their jump to the lands is always zero; another variable eliminated.
The tighter case necks grip bullets, the more pressure it takes to start moving them. 308 Winchester handloads may take 80 psi, 7.62 NATO service ammo is at least 800 psi.
Last edited by Bart B.; August 7, 2020 at 05:55 PM.
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