One more thing to consider: Hornady makes the Interlock SP in both flat base and boat tail versions; I have found more than a couple of rifles in my circle of influence that did not shoot the BT very well, but do very well with the flat base design. I usually try the BT first as its ballistics are a little better for long range, and generally if a rifle will shoot the BT well it will also shoot the flat base (although a slightly different POI). FWIW anyway.