This is a video I made for you new guys, demonstrating how I size my brass to get the proper neck and shoulder dimensions. You need not do it exactly how I do it with 2 dies; just take what you can from the video.
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<iframe width="480" height="360" src="//www.youtube.com/embed/uB6LA50Mie0" frameborder="0" allowfullscreen></iframe>)