one foot in the wildcats den

[mapper]

I think it is just a straight neck up of a 223 case, like the 6x45 so forming is just a trip through the die.

But that also means case capacities are the same.
Based on load data for 6x45 https://drive.google.com/file/d/0Bzu...FYMFQtRTg/view

I think a 87 gr bullet to go 3000 fps May be optimistic in the sharps.
Not saying it is not possible.

I'm seeing 2900 fps from a 24" barrel and h335 from the link above In a 6x45.

I wanted to stick to 6 mm with a 223 case so I did not look at any other sizes.
Just wanted to learn the process first.

Better performance would require more case capacity, and the 223 is about limited there.
Otherwise same case capacity and a higher bc bullet only goes so far.