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The Hodgdon Reloading site lists the .307 Winchester and has quite a few loads to try with different bullet weights. The Hornady manual also list the .307. I didn't check any further, but you should be able to find something that suits your needs.
I bet those bullets will grenade at close range though with that velocity, that is 300fps over what the 30-30 data is, which I believe this bullet is designed for.
I have not used them with a 30-30 let alone a 307 but that is just something that popped up into my head.
May be worth an email to Speer to see what their recommend on that bullet? They are great at responding.