I have gone through an evolution of thought and practice when it comes handloading. I have tried most of the ways to skin the cat and have come to the conclusion that plain ol basic reloading will get the job done very nicely. Case in point... I got a couple of used Senderos a few year back when I was just getting into LR shooting. A 300 RUM and a 25-06. For the RUM, I turned the necks, got the bushing neck and body die with the Comp seater and with the 25-06 I used a Forster FL sizing die with the BR micrometer seater. I did nothing to prep the Win brass I go with the 25-06 other than size it through the FL sizer. No pocket uniforming, no flash hole deburring, no turning and no trimming, just chamfer the inside and out side of mouth. It shot slightly better groups than the RUM to which I did all of the above. It may be that one rifle was just a little more accurate than the other rifle. In any case, the 25-06 did extremely well without jumping through all the hoops.
That said, I do uniform pockets and debur flasholes as it sure can't hurt and maybe help a little. I also trim after sizing after the first firing. These steps do add to consistency and are not difficult to do and consistency is very important in handloading
I spoke with with a Redding tech once about which sizing die I should get and he told me that in his opinion the best dies he has ever used were plain ole FL dies with expander ball. They gave him the best results with concentricity. Now it is possible to some runout with expander balls but properly lubing the inside of the necks, I have seen little to no increase in runout.
I just got another 300 RUM built and I will not be turning the necks of the brass for that rifle. I used a "match" reamer from PTG which has a .3435 neck and the OD of the bullet seated no turn necks is .336 Idealy the neck might be a little tighter and if I had to do it again, I would probably order a .341 neck, but it should do fine.
The benefit of turning necks is that it allows you to size without an expander ball and have a consistent ID for consistent grip and tension and it allows you cut a tighter neck chamber. However it is possible to have some inside irregularity after outside turning of necks. We're getting real nit picky. However, neck turning is a real PITA and it has never shown me any real benefit.
For me, the best effort to benefit result is to not bother with neck turning. order a reamer that gives me .004-.006 clearance with no turn necks and order a custom FL sizing die to size down ~ .003 -.004 less than seated bullet OD with expander to size up to ..001-.002 less than OD of bullet. This results in minimal working of brass and minimal impact to concentricity. I will probably get some Bertram 338 EDGE brass for its quality and neck it down. I will then order a custom FL die as described above.
This is the Long Range Hunting site and precision is critical here. However, the approach to BR precision is a whole different world although there are some similarities. Neck turning is the norm in the BR world were the slightest improvement in accuracy means the difference in where you place. It is also bench conditions vs field conditions.
