Neck Turning

[Ben]

For the past couple of days, I've been turning necks on my .222 cases.
I checked the neck thicknesses on several Remington factory cases with my tubing mike and found that they were averaging about .011 ".

I set my Hornady neck turning tool to .011" and started to work.
I want to shoot this " lot " of brass against other cases that ARE NOT neck turned with a proven accurate load in both so that the only variable in the test is .....neck turned or not neck turned.

Stay tuned.................

 

[Rick]

Curious, the brass was .011" and you turned them to .011". That should have cleaned up any part of any necks that might have been thick but in your picture it appears all necks had brass removed all the way around. Are they .011" now?

 

[Ben]

All are .011 now. Some were 12 , 13,14

 

[Rick]

Then to remove brass all the way around the neck they must have been thicker than .011" before turning right?

 

[Ian]

I expect you may find that reducing chamber neck to case neck clearance has a more dramatic effect on accuracy than does simply uniforming to the least common denominator. That would mean selecting the thickest necks you can find from a lot of brass and only touching the high side for no more than a 50% turn at most to both get better uniformity and an overall reduction in loaded neck clearance. Or use Scotch tape on the necks, AFTER you have a reliably accurate chamber impression.

 

[Brad]

I would rather select good cases by looking for minimal run out. Select a group where the thickness varies by less than .001 on the neck in a couple places around the neck.
When shooting high power the .001 or less were my 600 yard cases, .001-002 were 200-300 yard cases and the few worse than .002 were tossed.
Neck turning can sometimes mask a bigger issue. A cases much thicker on one side than the other can, over time, develop a permanent set as a bent case. Sizing won't remove it.
Selecting on minimal run out lets you have cases more likely to remain straight over time.

I think this is a worthwhile test. Will be interesting to see how time makes a difference too. Does one group shoot better over the long run, say after 5-10 firings.

 

[Ian]

Then to remove brass all the way around the neck they must have been thicker than .011" before turning right?

I don't know how you do it, but I rotate the neck all the way around and roll the thimble to follow it closely in order to find the min/max of each neck. I then sort those into piles based on the size of the minimum. There will usually be a few outright culls, a few that are thick all the way around, and two to three groups of turnable necks, depending on how I choose to sort.

 

[Ben]

I think this is a worthwhile test. Will be interesting to see how time makes a difference too. Does one group shoot better over the long run, say after 5-10 firings.

My thoughts also Brad.
It is an experiment for me.
We'll see how it turns out .

Ben

 

[JWFilips]

Very Interesting Thread. I will be watching the outcome. Ben, please keep us posted.

A tale of Woe here:
I have recently been bit twice with neck turning. Most recently I messed up a bunch of reformed Mil 308's to 243 because I thought they needed to be closer to commercial dimensions. When I fire formed them, the rounds were super accurate. Then I checked them after firing & they were all about .014. Comparing that to my Commercial Rem & Feds which were .011 I turned all of them to that thickness & they never shot as well ...with the same loads.

Alternately; quite awhile ago I had 75 beautiful 1953 FA Mil 30-06 brass that I reformed into 8x57 . I fire-formed those also And they shot great groups right from the start. after firing (I don't know what got into me but) I decided I needed to turn the necks on all of it ( no reason to... since I was sizing up!) But I did....& you guessed it! I don't use that brass anymore!
I won't be neck turning unless I see a problem from now on. Not really sure who opened my eyes "Ian or Fiver" but I know if I left all that brass alone I would not be posting here!

 

[Ben]

Jim,

Ummm, that doesn't sound good for the home team, now does it ?

I may have ruined about 25 nice .222 cases.
I guess we'll see ? ?

Ben

 

[Ian]

Ben, there's another monkey wrench caused by major neck turning: Concentricity. Your cases are formed, fired, and resized via outside forces. This pushes "excess" metal to the inside. When you trim the thick side off of the neck while piloting off of the inside, the outside and inside both are then no longer concentric to the case body and shoulder. It takes at least one good firing and resizing to correct this, so the first go after a turn should be considered a "fireforming" expedition at best. Don't draw conclusions until the second or third firing, and be careful even then as the necks are growing harder each time. Hard necks at low velocity/pressure can improve accuracy considerably if the loaded chamber neck clearance is extreme, provided of course that the inside of the neck is concentric with the throat upon firing.

 

[Ben]

The story of my life.........nothing is ever as easy as it 1st appears.

Ben

 

[Brad]

Anything worth doing is usually difficult. If it was easy then anyone would do it.

I still think it is a worthwhile study. Like Jim you may find it a fools errand but until you find that out for yourself will you ever really know?

Sometimes a man just has to go out and investigate.

 

[Ben]

I'm one of those that will learn by doing.

Sometimes, they are painful lessons, but I still learn.

Ben

 

[Brad]

I think we all are like that. Seeng is believing. Sometimes you just have to hit you own thumb with the hammer to really understand that it hurts.

 

[Ben]

I guess the most I have to loose in this one is 25 ea. old tired .222 Rem cases.

Could be worse......................

Ben

 

[Ben]

While I'm at it, I plan to investigate the likelihood that 1 lube groove filled will out shoot 2 lube grooves filled. Bullets will be the same identical diameter ( .2255 " )





So far ( in VERY limited testing ), the Lyman 225462 has been the clear leader in the accuracy dept. Now, to see if we can " fine tune " things a bit ? ?

This is the group with the 225462 from 4 days ago :

 

[JWFilips]

Ben,
One thing to keep in mind ...I do not have the precision neck turner as you do. I just use a Lyman outside turning tool on the Lyman Case trimmer.
Not exactly precise ...It has a lot of runout. My turned necks are never an nice as what you showed here. Some will look somewhat good . some look 20% turned, and some come out gouged. Good tools make the effort worth while. My gut feeling is you will be golden. After all the sako chamber is far better then anything I'm shooting.
I'm really interested in your results ( using quality tools & chamber)
I had a Sinclair neck Turner in the 80's when I shot benchrest but Sold that a long time ago! Sure wish I had it back!

I'm always doing my best to get my pan full enough of lube to get all the grooves filled ( I pan lube) Why only fill one groove?
I'm curious
Jim

 

[Brad]

In many situations filling one groove gives better accuracy than filing them all. One prime example is 38 special wadcutters.
At lower velocity I bet one groove is more accurate, especially wth a lube like BR. As speed and pressure go up a second groove may be better but only range time will show the facts with your combination.

 

[JWFilips]

Great ...Another variable to add to the list!