You need this to reload .45 acp - Lee Carbide Factory Crimp Die .45 ACP/.45 Winchester Magnum 90864

This is a specialized crimp die that ensures all your .45 ACP reloads will chamber properly. Like an insurance policy, run each one throught this die, and take the guesswork out of you finished product. I should have ordered my original die set that included the Factory Crimp die, but as I learn more about reloading, and have more experience, I realized that's it's just good practice to make sure your finished rounds are precisley the correct size.