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brass under trim lenght after firing?
ChetStafford
Member Posts: 2,794
I've got brass that is under length for trim length what is the deal?do i have my dies set wrong or is this common with full length resizing? trim is 2.815 my brass is 2.797 I dont get it [:0]
Comments
The new cases you shot had a case body diameter that was narrow up by the shoulder. Your chamber may be a bit large near the shoulder, but has tight headspace. Upon firing the shoulder gets blown out, it need nmaterial to move out. Since the headspace is fine it gets it's growth brass from the neck area.
Thats my story and I'm sticking to it. [:D]
I bet the next time you fire them they get longer.
Like Bpost mentioned, the chamber is probably just loose enough to cause the brass to end up shorter bvecause of the internal space involved.
I'm inclined to go with Bposts explanation. The Brass flows backward while being shot and shortens itself. Usually, the trimming process is done after resizing a fired case. That way you have the form fit and get it to the length you want. HERE's THE CATCH..during the sizing process many people don't adequately lube THE INSIDE OF THE NECK...brass stretches like no yesterday. Minimize this and you minimize trimming and lengthen case life considerably. I soak a q-tip in my lube stuff and swirl it in each case neck. It never hurts to give your sizing ball a whirl either, Saves probably .002-.006 per resizing. That's my story of where your brass goes. -good luck.
I'm inclined to go with Bposts explanation. The Brass flows backward while being shot and shortens itself. Usually, the trimming process is done after resizing a fired case. That way you have the form fit and get it to the length you want. HERE's THE CATCH..during the sizing process many people don't adequately lube THE INSIDE OF THE NECK...brass stretches like no yesterday. Minimize this and you minimize trimming and lengthen case life considerably. I soak a q-tip in my lube stuff and swirl it in each case neck. It never hurts to give your sizing ball a whirl either, Saves probably .002-.006 per resizing. That's my story of where your brass goes. -good luck.