It's a pretty simple question I guess. If human error were factored out, is neck turning the difference between .5" and .1" groups at 100 yards? Or is it more like meplat uniforming/pointing (evidence in both directions)?
It's a pretty simple question I guess. If human error were factored out, is neck turning the difference between .5" and .1" groups at 100 yards? Or is it more like meplat uniforming/pointing (evidence in both directions)?
My current barrel is a Bartlein 0.30 cal 308Win 9"twist 5r. Do you know what kind of reamer GA Precision would have used? Would it be a Bisley Match? It chambers lapua brass just fine.
You cannot gain much with a big sloppy neck as most factory rifles have.
The object is to guide the bullet without much variation.
If the chamber neck is large and cannot guide the case neck then you lose alignment between the case and the chamber. The bullet can move off center in relationship to the bore.
So if one's preferred load is jammed hard into the lands, will neck turning still make a difference?
There is no such thing as "no turn brass". No brass mfgr lists "no turn brass".Jason,
I shoot exclusively 100 yds in several calibers. I've tested all my calibers with turning necks and not turning neck. IMHO, turning necks will NOT make a difference, except to clean up the necks (concentricity) for shooting @ 100 yds. The ONLY exception is where you have a tight chamber and you are looking for a .002 clearance or to be able to close the bolt. Lapua has changed the thickness of most of their brass to accommodate and do away with the need to turn their brass which is why they call it "No Turn Brass." Personally, for precision shooting purposes, I still "clean up" all my new brass strictly to insure concentricity. But for general shooting purposes like hunting and recreation, you are wasting your time and money by turning brass.
Alex
There is no such thing as "no turn brass". No brass mfgr lists "no turn brass".
There are , however, no turn chambers.... cut with reamers built for a specific OEM brass.... The "standard "no turn" .272 neck on the BR/Dasher comes to mind where loaded rounds come in at around .2695 - .270. when loaded with blue box Lapua brass.
For the record I don't turn necks, so no ax to grind. So you are saying, outside of providing adequate neck clearance, turning does no good for accuracy?If by "make a difference" you mean "improve alignment of bullet with bore" the answer is "no". But the answer is also "no" if the bullet is jumping.
The case neck proper cannot center the case in the chamber, or the bullet in the bore, since there must be clearance around the case neck to allow the neck to expand and fully release the bullet. Ideally the outside of the case neck proper should not touch anything. If you're going to shoot a rifle with the chamber walls hugging the outside of the case neck, let me know where, so I can arrange to be elsewhere.
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If there is enough chamber neck clearance around the neck to allow safe expansion of the neck upon firing, then the chamber neck cannot be guiding or centering the case in the chamber, or the bullet in the bore.
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