To neck turn or not to neck turn

duckdog

New member
I recently purchased a Forster neck turner. I was always under the impression that if you turned your necks so they were true all the way around, it would help your accuracy. Now after reading the godawful instructions /ubbthreads/images/graemlins/angry-smiley-055.gif, they say to turn your necks until you reach the cartridge neck dimension. Well, all my fired, sized, cases are well below cartridge neck dimension maximum. I don't know whether to go ahead and "even" them up, or just wait until they grow fat and then turn them. /ubbthreads/images/graemlins/confused1.gif What's your advice?
 
I usually don't turn them unless they are within about .002" of the max, with the bullet seated, ...... unless I have a chamber with a tight neck. Or, if they are over .0015" variation in thickness around the neck.

I have some Federal Match .223 brass that I have never had to neck turn, while my Rem. 22-250 often required it, due to the brass being lower in uniformity.

And, unless the brass is quite a bit out, or overly thick, I only turn the brass so that I take brass off the thicker half of the neck, rather than all the way around, so I don't unnecessarily thin the brass at the neck.
 
Forster really contradicts themselves here. On the directions for the neck turner that mounts to the trimmer set up, it reads: "Adjust the carbide cutter acordingly to obtain the proper neck diameter setting. [case necks frequently have high and low spots, so don't be concerned if the proper outside neck diameter is achieveed without removing brass from the entire outside diameter of the neck.]

The direction for the handheld outside neck turner read: Turn [the case] slowly enoughto provide a smooth, even cut over the entire case neck's diameter.

Never mentioning anything about referring to a manual for your given caliber for neck diameter set by Saami.
So, how important is this dimention. I realize being too big is obviously a problem, but what are the tolerances of being too thin.
 
Neck turning is kinda going out of style.

At one time, it considered "by the cognoscenti", to be mandatory - but the current thought is not to neck turn, or to turn the least amount (skim the high side off).

It is extremely rare that you will find necks that are thicker than SAAMI, cuz SAAMI is the MAXIMUM allowable, and cases are not made that thick at the factory.

Set up the turner and bring down the cutter until the high side is removed, and you have cut about 90% of the neck to shinny - this will clean up all your cases, without making them TOO thin.


.
 
Quote:

Never mentioning anything about referring to a manual for your given caliber for neck diameter set by Saami.
So, how important is this dimention. I realize being too big is obviously a problem, but what are the tolerances of being too thin.



The only personal example I have is when a friend was shooting his Ruger M77 in .220 Swift. He used Winchester cases when he started loading for it, and they worked fine. But, he only had about 40 of them. Brass was hard to get at the time and finally, some Rem. cases became available through Midway. He bought a couple hundred of them.

He worked up a load for the Rem. cases. The second time he loaded and shot them, he was getting sticky extraction and flattened primers. When we measured the case necks, the OAL length of the cases was fine, but a bullet wouldn't drop into a fired Rem. case. It turned out the new Rem. cases were about .003" larger in diameter (with a seated bullet) than were the Win. cases. He had a minimum dimension in his rifle in the neck area and when the brass flowed on the shot, with the Rem. cases and their thicker neck brass, it was enough to make the neck too tight to expand and release the bullet properly on firing ...... hence the evidence of high pressures.

So, he used my neck turner on his Rem. cases to turn the necks down and the problem was solved. The .220 Swift is well known to cause brass to thicken at the necks more rapidly than many other cartridges.

I had purchased the neck turner after I had to pound open the bolt on my .22-250 Rem., when thick case necks caused high pressures. I had never had that problem before and I was inexperienced enough at that time to not check the brass thickness by trying to drop a bullet into the fired, but unsized case. If it doesn't go, the brass is probably too thick to release the bullet properly and the necks need turning for safety reasons.
 
I've never done it and it shouldn't be necessary with a factory mass-produced rifle (like mine are).

Custom rifles (maybe sometimes mass-produced as well) can have tighter tolerances and may need to be turned.
 
If your using bushing dies cleaning up the necks will provide more uniform neck tension. I've kind of followed Sinclair on doing 70 to 80% of the neck thickness and you need a pretty good ball mike and feeler gauges to set cutter neck thickness.

Not all chamber are cut to reloading manual spec the fired case will give you outside neck dia on your chamber.

Might want to read this may help
http://www.varmintal.com/arelo.htm
 
I have several tight neck rifles I have to turn for, and one factory rifle I have to do it for, just as above, my 220 swift, a remington classic, also gets thick necks after about 2 firings. taking a little off the neck takes care of this. I would not do it for any factory rifle if I did not have to, and have no reamers, but am set to turn necks for 22 and 6mm.
Barry
 
Quote:
what causes runout on the case neck?aftervresizing with forster fl die


The biggest cause of neck and loaded ammo runout is uneven case wall thickness. The thicker side springs back more than the thinner side.

Jack
 
Quote:
so if you want to reduce runout you have to neck turn


No. If you want less runout you have to use brass that has consistent wall thickness. Neck turning will do little or nothing to reduce runout. Wall thickness affects the whole case not just the neck.

Jack
 
JR, really! You don't neck turn!

Maybe a lost art it is, You know old school!

It's to bad Lapua or Norma doesn't make it all!

I've got a good run of .223 brass from a source here that just kind of gives me some!

UMC crapolla! But I put them through the runout test and I probably throw 25% away!

If they, (Make the grade!) .0015 TIR! I load em!

Refurbished cases are different! I won't get into case annealing here!
 
I only neck turn when using bushing dies. This is to get consistant neck tension. On the cases I use a standard sizing die with a neck expander, I do not bother with it.
 
Back
Top