01-05-2020, 04:32 PM
SightedIn Wrote:I believe it is aluminum, but its not C shaped, its continuous all around, sort of a square shape
SI:
Your JP rifle will not all of a sudden lose its headspace and unless you can physically move the barrel around with you hand -- look at your press and your lube.
Like A5B, I suspect the Lee press is giving you too much spring back and it is causing some real inconsistent amounts of pressure on your brass. I too have a Lee press and I use it for simple things like decapping or pulling bullets. I would trust it for sizing straight walled cases but not for any sort of sizing that needs any pressure like bumping does. Been there and done that with a Lee press.
Also, if your lube is home made it may also be the problem. I have found the home made spray lubes to be inconsistent and you could be getting an inconsistent amount of lanolin on the necks. That can cause huge differences in headspace when bumping.
LR55