Neck Turning. Expander mandrels and resizing

[pigsy]

Given the current situation and additional time on hands, I've decided to go down the possible rabbit hole of neck turning.

I have the K&M tools, including the expanding die and mandrels (6.5CM and .308).

LOTS of info on the web, German Salazar's guide on Accurrateshooter.com being very helpful. However, I have a few additional questions that hopefully the collective knowledge on FB can shed some light on. I'm only shooting factory barrels/chambers (Howa 1500 in .308 and Remington 700 in 6.5CM) so do understand that perhaps the benefits are minimal.

My process so far is:

1. Clean & Full length resize (Lee Dies)
2. Trim to length (Lee cutter)
3. Lube and run through K&M expanding mandrel
4. Set up turning tool/cutter and turn necks
5. Wipe down brass to clean from sizing lube
6. Prime/powder etc

So my questions that have come out of doing this on the first 50 cases are:

1. Do you need to neck turn the full diameter of the cases or just take off the high spots?
2. Do you need to resize again after neck turning (possibly just neck resize - Lee collett die)?
3. Is there any advantage to concentricity to use the mandrel expanding die in all reloading situations (prior to Full length resizing)?

Hopefully that's clear (ish) but any advice would be gratefully received!

Cheers

Adam

[The Gun Pimp]

Given the current situation and additional time on hands, I've decided to go down the possible rabbit hole of neck turning.

I have the K&M tools, including the expanding die and mandrels (6.5CM and .308).

LOTS of info on the web, German Salazar's guide on Accurrateshooter.com being very helpful. However, I have a few additional questions that hopefully the collective knowledge on FB can shed some light on. I'm only shooting factory barrels/chambers (Howa 1500 in .308 and Remington 700 in 6.5CM) so do understand that perhaps the benefits are minimal.

My process so far is:

1. Clean & Full length resize (Lee Dies)
2. Trim to length (Lee cutter)
3. Lube and run through K&M expanding mandrel
4. Set up turning tool/cutter and turn necks
5. Wipe down brass to clean from sizing lube
6. Prime/powder etc

So my questions that have come out of doing this on the first 50 cases are:

1. Do you need to neck turn the full diameter of the cases or just take off the high spots?
2. Do you need to resize again after neck turning (possibly just neck resize - Lee collett die)?
3. Is there any advantage to concentricity to use the mandrel expanding die in all reloading situations (prior to Full length resizing)?

Hopefully that's clear (ish) but any advice would be gratefully received!

Cheers

Adam

Neck turning was originally conceived by the early American benchrest shooters because the (often surplus) brass they were using was so inconsistent in the neck BUT they also realised that making the brass thinnner would obviously increase the case-neck-to-chmber-neck clearance - which is detrimental as it doesn't help to 'centre' the bullet in the bore. So, to get the best out of neck-turning - a tight-neck chamber is essential.

Modern quality brass like Lapua is so good however I no longer neck-turn it even for 1000 yd benchrest competition but, I still neck-turn for my short-range 6PPC benchgun and run a tight-neck chamber with about 0.002in. clearance. With regard to case-sizing - always full-length size but remove the expander ball (or grind it down) and upsize the neck with a mandrel.

[pigsy]

Many thanks.

Seems therefore that the process may well be pointless in my case, but always great to know where and why the practice got adopted.

Much appreciated!

[DaveT]

Using a mandrel as the final operation to set final neck tension will push any neck wall thickness variances to the outside (not likely to be any significant variance with Lapua anyway).
It therefore won't touch the chamber wall in the neck area on a normal (ie not tight neck) chamber so is largely irrelevant unless the wall variance is severe..

[WelshShooter]

Excellent post by The Gun Pimp. My understanding has always been the same, it's an activity reserved for tight neck chambers. There are plenty of other activities which you could concentrate on to improve precision before neck turning in a regular chamber.

If you're really that bored and are looking for something to fill the time, why not consider meplat trimming and pointing? Try a search on here because I think Ovenpaa has actually done this and provided real life measurements down range (or at least referenced some results from someone else, I can't remember). I'm pretty sure he used a labradar down range to calculate the improvement in ballistic coefficient? Uniforming the meplats has interested me but I've never gone into it because I haven't had the opportunity to shoot long range for a few years now and it's a pointless exercise (pun intended) for 100m shooting.

[pigsy]

All great advice!

It could be said that I would get bigger benefits from spending more time shooting than worrying about the minor points or reloading.

However it seems that for some reason the gains I had when I first started reloading have all but disappeared!

[Sim G]

I do think that the accuracy of brass, Bullets and ultimately rifles, is a testament to the advancement in materials and tolerances. Even a cheap rifle, off the shelf, with off the shelf components, will provide a level of accuracy that 30 years ago would have cost thousands of pounds!

I certainly do get the attraction of jumping down certain “rabbit holes” but in invariably today, for those of us with average gear and average skill, it’s got to be for academic or entertainment primarily in mind.

[pigsy]

And I think that's nailed it for me - both entertainment and academic reasons.

Although the more variables I remove from the reloading equation starts to make my shooting look at best, quite inconsistent!