The lead .361 bullets are just a little fatter than jacketed bullets , that's why you see the slight expansion . Normal and OK !
Actually that's good ... the case is gripping the bullet tightly .

If the lead bullets wants to creep forward during shooting , apply a bit of crimp to the bullet to hold it in place .

Lee carbide dies all tend to size on the tight side so they will grip the smaller diameter jacketed bullets (.360") tightly , it's common .

Loads are looking good ... it's range time !
Gary

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