BTW… buy some LC or LC match brass for semi-handloads. It’s really rigged brass and made for semi- and full-auto use.
Save the Hornady for your bolt guns!
Sirhr
Use LC brass, and more moderate loads. The small improvement in consistency with good brass like Lapua/Alpha/etc is lost in the noise of a semi auto.
LC brass is much more durable, especially in the case head. Even without a small (high pressure) firing pin, I have fired LC brass up to 10 times in a LR-308. Hotter loads would still crater the primer a bit, but I never blanked one.
Service rifle load data is your friend. Plan for velocities around 75-125 fps less than a bolt gun of the same barrel length.
I have never used a small base die. Just a generic RCBS full length die has always proven adequate, and does not overwork the brass. This may depend on your exact chamber.