Neck turning Brass - question

[croc4]

When neck turning brass, how far is too far?, do you turn the neck until the neck is all shaved evenly (all shiney new brass), I tried a few test shells last night and noticed that there were still a few small places that were not touched by the cutter, and wasn't sure how far was too far when trimming the necks

[Mike Irwin]

Are you talking about shaving the neck to reduce the overall length and square the case mouth, or are you talking about shaving the neck around its circumference to provide proper chamber clearance when a round is seated?

[croc4]

I'm refering to shaving the thickness of the brass in the neck area, to make sure that the thickness of the neck is uniform. This improves the bullets contricity when seated in the shell amoung other things

[CTC01]

When I set the neck turner (Forester) up I start by getting the cutter set so it has cut at least 1/2 to 3/4 around the neck. This has worked very well for me. Usually gets neck concentricity down under .004" (close enough for service rifle ) It is possible to take off too much, be careful I have trashed a few cases.

[Foxman]

The acknowledged wisdom is to set your cutter to just turn roughly half way round the neck, this leaves it still thick enough to properly grip the bullet when standard dies are used. If you set it like this it will do for all cases of the same make. If you take off more the std dies will not provide enough grip to keep the bullet in place particularly if you put several rounds in the mag, each time you fire it will push the bullet back into the case, causing various problems like high pressure etc. Match shooters use special dies to suit the amount the turn off and ususally are only loading one round at a time. I do mine as above when the case is new and leave it at that and get good accuracy from it.

[amamnn]

Once you have checked your brass for concentricity, and found it to be off, the next check on the neck is to check the neck walll thickness. If the neck is thicker on one side, make a mark on the shoulder there with a felt pen. You now set your neck turning tool to gently but firmly touch the neck on that low side. After cutting, check the thickness again. If you have set your tool correctly, you should be done. You may see spots that have not been cut on the low side.
Turning the neck without checking the actual thickness of the neck wall is not going to help a lot if you don't know how much to take off and where. Also, neck turning does nothing at all to help if the neck is just cockeyed due to the brass not shrinking back uniformly after firing.

[amamnn]

oops I meant to say to set your neck turning tool on the marked (THINNER) side of the case, taking care not to shave the shoulder.

[918v]

I turn 2/3 of the neck for thickness. The case then goes into a neck-ream die and I ream the inside, thereby forming the perfect neck without any internal or external flaws. Subsequent doughnouts are easily removed by reaming the neck in the die, and the die FL sizes too.

Or,

You can buy Norma brass or Lapua for alot more. My dies have paid for themselves several times over.

[joneb]

A tube thickness micrometer should be used to check case neck thickness, when there are variations it's usally through out the whole case. A bench rest shooter would toss the brass, but they scrutinize the best of brass culling for a few grains of difference in weight. When working up loads I will index the cases, so that the case is orientated one way from sizing to firing.

[amamnn]

I used to toss any brass that was too thick on one side until a friend mentioned that he had done a side by side test of .30-06 brass that he'd turned and brass that had not needed turning. All the brass was identical in size and weight. (within .002" head to shoulder and neck length, and .5 grains in weight) He said he'd found no significant difference in 10 rounds of each.

I had to save up brass to get that many out of thickness and that close in weight, but eventually I was able to duplicate his experiment. Now I shoot the cases I have neck turned as fouling shots, but if I were hunting or not competing, I would have no problem using those cases just like the others.