So today I recieved my Porters products collet die and mandral assortment. Just so happened I have some brass that I full length resized without the expander ready to go. (Done on a Foresters FL NON bushing die). I checked the runout on the necks and was getting arount .001 runout.
So I setup my die, selected my mandral to give me .0015 neck tension and away I went.
Checked the 1st round and the tension was right on. Checked the next few and again perfect.
So I ran 25 or so cases, pulled out my runout gauge and nearly fell off my stool.
Good cases are now about 003 runout. Bad ones are 005!
So, someone educate me. The process I thought went smoothly. Little lube, and not much effort running the press.
Could it be I have to take smaller bites and say set the tension to .003 first, then down to .0015?
Lapua 308 brass if anyone is interested.
Thanks!
So I setup my die, selected my mandral to give me .0015 neck tension and away I went.
Checked the 1st round and the tension was right on. Checked the next few and again perfect.
So I ran 25 or so cases, pulled out my runout gauge and nearly fell off my stool.
Good cases are now about 003 runout. Bad ones are 005!
So, someone educate me. The process I thought went smoothly. Little lube, and not much effort running the press.
Could it be I have to take smaller bites and say set the tension to .003 first, then down to .0015?
Lapua 308 brass if anyone is interested.
Thanks!