I am moving some case prep from a Dillon 750 to a zero press and am not "feeling" the mandrel expansion much at all. I didn't notice it on the Dillon as I was simultaneously sizing cases. I've been using a mandrel (Porters Precision Die and gage pins) sized .002 under the bullet diameter to achieve the recommended seating fit or "tension". (I know tension may not be the concise term so please pardon my use of the term here for expediency.) I've also been interested in experimenting with more tension based on some reading.
With SAC dies for 6.5mm I'm using a .288 bushing so with neck wall thickness of .013 I should be getting an inside neck diameter of .262 prior to the mandrel which is what I want for .002 tension but there isn't much, if anything, to expand with the mandrel. I don't feel much, if any, resistance with the .262 pin. Maybe I'm just throwing a hot dog down a hallway? Before I buy a bunch of bushings and pins I don't need I wanted to see if some of you have experience with this.
Should I get a .287 or .286 bushing to allow for springback to ensure the pins actually expands the neck a bit or will I just overwork the brass? Brass is annealed with my AMP prior to sizing.
Also, thoughts on .0025 or .003 tension?
Thanks in Advance!
With SAC dies for 6.5mm I'm using a .288 bushing so with neck wall thickness of .013 I should be getting an inside neck diameter of .262 prior to the mandrel which is what I want for .002 tension but there isn't much, if anything, to expand with the mandrel. I don't feel much, if any, resistance with the .262 pin. Maybe I'm just throwing a hot dog down a hallway? Before I buy a bunch of bushings and pins I don't need I wanted to see if some of you have experience with this.
Should I get a .287 or .286 bushing to allow for springback to ensure the pins actually expands the neck a bit or will I just overwork the brass? Brass is annealed with my AMP prior to sizing.
Also, thoughts on .0025 or .003 tension?
Thanks in Advance!