Same primer, different powder

[boxhitch]

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[Dogleg]

check your headspace while sizing your brass. It is possible to oversize brass if you have a sizing die that can oversize brass or if you have a loose chamber in the rifle.

A 30-30 head-spaces on the rim, so over-sizing doesn’t increase headspace beyond that point. If anything it will give the firing pin something more substantial to hit, compared undersizing a heavily tapered case landing in a heavily tapered hole.