Carlos Hathcock
.450/400 Nitro Ex
True. I guess if there were an "indent" in the neck the ball would shape that back to round. I dont know that it contacts on the up stroke since it's already expanded from firing. Will play around with this.Never thought about this. On the downstroke the ball is in the case at the bottom of the stroke. On the upstroke the ball does make contact with the neck. I think it may just be for concentricity of the mouth if you have one that is bent? The way to test would be to size a piece of brass with the pin and one without then measure the mouth openings. I'm leaning towards concentricity since I know that you can load ammo sizing brass without the pin.