Neck Turning?

[diderr]

I've been reloading for about 7 years now, but never looked into neck turning. And im almost ashamed to admit I dont know what it really does. I clean, anneal, size, trim, dechamfer, but do not neck turn. It cant be THAT important if I've gone this long w/o issues right? Can someone please break it down to what it does?
Thanks.

 

[el matador]

I'll break it down a little. Factory cases have necks that aren't entirely uniform in thickness all the way around. Good quality brass such as Norma or Lapua is often within .001" from thickest to thinnest, but lesser brass can vary by several thousandths. And one brand is usually thicker or thinner than the next regardless of how uniform they are. Neck turning is the process of machining brass off the outside of the neck (neck reaming takes it off the inside) in order to create a uniform, specific neck thickness. Some custom chambers have very tight tolerances and need to have the brass slimmed down or the rounds won't even chamber. In most rifles with SAAMI min chambers, or factory guns with sloppy chambers, this isn't a concern. In these cases the advantage of neck turning is to create uniform neck tension from round to round and also concentric tension in each individual round.

There are about a hundred different things you can do to enhance your accuracy and neck turning is just one of them. It may help immensely in some rifles and it may do very little in others. Generally speaking though it makes your ammo more consistent and thus more accurate.

 

[Canadian Bushman]

Im gonna say el matador hit it on the head.

 

[AZShooter]

I agree with Matador.

I would like to suggest to the OP that if you turn necks for a factory chambering you may reduce neck life by causing overworking of the brass causing the necks to split.

The reason was touched upon by Matador. A factory SAMMI chamber has to have ample room for bullet release with a variety of different neck wall thicknesses. If the brass is thinned down with an approximate 80% skim turning the thinner brass has to expand more when it makes contact with the chamber wall during firing. Then sizing especially with a FL die with a sizer ball over sizes the brass. This is called working the brass and it will work harden causing splits in short order. I know I did it with a 284 win and it only took two firings.

Should you decide to skim turn the necks you should use a bushing die so you can maintain proper neck tension. Use of a sizer ball FL die will end up with less tension.

Gets complicated huh?

Now if you decide to put to use a custom chamber reamer then neck turning can be worth your time.

James O'Hara is featured on accurate shooting right now. He says: "Some competitors don't turn necks, but without uniform neck tension you will have vertical." He is a 1000 yd competitor.

Daily Bulletin

You can read quite a bit on neck turning here:

neck turning « Search Results « Daily Bulletin

 

[Timber338]

Matador and AZshooter are both right. I"ve just got a few more points to add in case you decide you want to do it. I went down this road several years ago and spent alot of time on the phone with the guys at Redding and they passed along some very helpful info.

Based only on numbers, you want to find the brass with the single thinnest wall thickness and turn all of your necks down to that number so every neck is the same with all of your brass. But generally speaking, any variation that exists in the neck of the case is also going to exist in the body of the case as well ... which you cannot turn away. So cull out the cases with the very thinnest necks if they are out of family from the rest of the brass. Along these lines, you dont have to turn the brass away from the entire neck wall as long as you are within .001 all the way around. this will keep a bit more thickness in your brass and you'll still be achieving your goal. you might only remove 75% of the brass leaving the other 25% untouched as the cutter turns around the neck.

But then the point I reached with case turning is that you just cannot completely fix brass that has large variations in wall thickness because of the variation that will likely exist in the body. So although my particular rifle shot much better by turning the necks, I just decided to spend more money on brass and not deal with the hassle of turning. Sometimes this is not an option if your cartridge is not offered by one of the higher end brass manufacturers.

 

[Truc]

to put it simple, if you have a tight neck chamber (which you don't) then turn them and buy a bushing die.
all other chambers just buy Norma or Lapua brass and be done with it.

 

[Timber338]

to put it simple, if you have a tight neck chamber (which you don't) then turn them and buy a bushing die.
all other chambers just buy Norma or Lapua brass and be done with it.

haha. well put. I have been using Nosler brass, dimensionally it is very consistent all around.

 

[idaho elk hunter]

haha. well put. I have been using Nosler brass, dimensionally it is very consistent all around.

Nosler brass is sorted and weighed Federal brass. Good stuff but is not in the same Quality as Lapua or Norma. For belted mags Hornady is the brass to use. EVERYONE in the competitive shooting sport has caught on to this. To reaffirm this check out precisionrifleblog.com. I THINK this is the site. We have a handful of us here that shoot 1000 to 1500 yds and always do better with this brass with very little prep. Use Winchester brass fully prepped for hunting and it still does not equal the accuracy in ALL of our rifles. It is much cheaper and gives a LITTLE more velocity, not that it makes a difference, but every little bit helps in the velocity department. Hope this helps on the expensive NOSLER brass.