Thread: Case neck sizing and effect on accuracy

I've found in my 22hornets neck sizing appears to make a difference in consistency accuracy wise

Yep, my 22k Hornet is really particular about reloading technique. It is pretty straight forward to load and get ~1MOA with it but to consistently get under that is not so easy. Perfect powder measuring, case sorting, neck tension... Small case throwing a relatively heavy projectile I suspect ensures little inconsistencies show themselves.

Originally Posted by Puffin

Then there is the question as to how much of the neck provides the ideal support for the bullet. Do long necks aid accuracy as is often proposed? If so then why have the bullet only supported by a fraction of the available neck? Maybe the advantage of long necks is to allow for both a section of neck left unsized for the above mentioned “centering” but with 4-5mm still left for the bullet? Maybe long necks aid accuracy only by a beneficial effect on throat erosion?

An ideal bullet situation in this regard would be a bullet of sufficient length to (a) benefit both from the support of the entire neck length (provided the case chambers concentric with the bore axis), and (b) still reach nearly up to where it engages with the rifling. Reason: bullet axis coinciding with bore axis means less wobble, and so less spread. The advantage of neck sizing only has all to do with the centering of cases in generous chambers. No point of course only neck sizing a case that has been fired (read fire-de-formed) to become forever non-concentric.

Originally Posted by Gillie

Yep, my 22k Hornet is really particular about reloading technique. It is pretty straight forward to load and get ~1MOA with it but to consistently get under that is not so easy. Perfect powder measuring, case sorting, neck tension... Small case throwing a relatively heavy projectile I suspect ensures little inconsistencies show themselves.

I have been lucky with mine shoots anything well with bugger all fuss.

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https://www.youtube.com/watch?v=lLG2kSrD40g

Originally Posted by chalkeye

https://www.youtube.com/watch?v=lLG2kSrD40g

Competition rifles such as BR and custom chambered target rifles invariably have tight chambers and necks where case expansion is minimal on firing. Full length resizing on those rifles is quite common now in competition circles. Factory hunting rifles have larger tolerances for obvious reasons and the brass will certainly get worked more and have a shorter life with FL sizing.

Even so, for hunting I prefer to FL resize to avoid any hard to chamber rounds. For target shooting with a hunting rifle such NZDA events etc. I neck size with a Redding type S bushing die or Wilson hand neck die and use a Redding body die when the case begins to get harder to chamber. This is not so much for accuracy sake but more so for brass longevity.

It obviously all depends on the individual rifle too.

As Eric mentions, you only need to FL size enough to bump the shoulder back 2-3 thousandths.

If you are using a FL die and bumping the shoulder then you are full length sizing, nothing partial about it.