04-29-2020, 12:11 PM
tdbru Wrote:when you neck down, the neck wall thickness increases so you end up needing to do neck turning to restore correct neck thickness. some do inside turning (reaming), others do outside neck turning to get the neck thickness to the correct value. as almost everyone has said, we did this when Grendel brass was hard to get. it's quite time intensive so now that correct brass is more readily available, it just doesn't seem too time efficient to do other than educationally to me anymore.
-tdbru
Never had to neck turn one round and I used the tighter of the Grendel Chambers.
I did use a .289 neck sizing collet though because yes, the neck walls are thicker. They still chambered just fine in the tighter match chamber.
In fact, when we had to use the 7.62 X 39 brass, I do not recall anyone neck turning it.
I was the only one who ran an internal reamer through them to take out the donut. I think this gave me one more shot before primers fell out of the primer pockets.
Yes, the brass was thicker. Yes, it probably caused higher pressures. Yes, it worked. But no one really cared if they lost any, either
Not worth the time spent neck turning but may be worth the time to take out the donut.
LR55