Runout tolerances

[bosulli]

I had started a thread about neck turning, but appears I need to know more about run out.

I just got a Sinclair concentricity gauge to assist in neck turning procedures.

Appears my Hornady emptied reloads sometimes have runout of .004. Some have .002. I found a loaded hornady that had not been fired. Runout was .001.

My unfired nosler empty brass is .002. My many times fired 300wm winchester brass is at .001.

First, I am reading the gauge correctly that the graduations on it or .001?

Second, how much tolerance should I accept, if I shooting for long range precision.

Thirdly, In prior posts, I was told that its either my chamber or die. Can anything be done? The 223 is a douglas barrel chambered by Compass Lake.

 

[Unsichtbar]

Re: Runout tolerances

Is this .223 a gas gun that Frank for you built?

 

[myerfire]

Re: Runout tolerances

I try to stay under .002 runout. I checked some FGMM (308) and it varied from .001 to .009 in the particular box I had.
myerfire

 

[bosulli]

Re: Runout tolerances

.002 does seem to be a good tolerance.

I measured the neck on an unfired Nosler case - .001.

Ran it thru the Lee resizing die, and the runout was .004.

So, it must be the die.

Measured the decapping pin in several places, and no runout. The shell holder seemed to be aligned with the die. I am guessing the decapping adjusment nut is not holding it sqaure.

Try a new die, or repair the current one?

 

[Victor N TN]

Re: Runout tolerances

This may be a case of "you get what you pay for."

 

[Rookie]

Re: Runout tolerances

I also recently purchased the same gage. I've been reducing runout to within .002. Loaded 150 rounds so far using the gage, and have produced the worst groups I've ever experienced with this rifle. I'm at a loss.

 

[bosulli]

Re: Runout tolerances

I am going to get the Redding dies for my 300wm. Dont want to spend $150 on dies for 223, but if they are causing out of spec runout, I have to do something. I have a Lee 6.8 die, and will swap out the decapping pin and see if that resolves the problem.

 

[Victor N TN]

Re: Runout tolerances

Before you go "hog wild" and buy stuff you may not need, have you checked UNSIZED brass after it has been shot? I would be inclined to buy a standard Hornady, RCBS or Redding F/L die set and adjust everything from scratch and see how that works. Then if you NEED to go with more expensive dies, have at it.

I'm a really big fan of the Redding "S" F/L sizing die and their Comp. seater. But you can get buy without them. It takes more time and is a bigger hassle. But you CAN do it. The main thing is quality if you're going to shoot either really small groups or very long range.

Good luck.

 

[bosulli]

Re: Runout tolerances

Thanks Victor.

I will be investing in better dies for my long range guns. I have been shopping and reading up on the Redding dies, and will have post soon asking about them.

I did swap out decapping adjustment pin nuts with a 6.8 Lee die, and the runout went down to .001. The old nut had some grit in it, which prevented it from closing down correctly. I cleaned it, and with the old 223 die adjustment nut, runout is .002.

Now, I can get back to the neck turning post that led to this post.

 

[Greg Langelius *]

Re: Runout tolerances

There may be less to gain if you're shooting with SAAMI spec chambers. They are loose/sloppy enough that issues like concentricity and neck turning don't really have such a major effect on accuracy. Yes, there's some accuracy tradeoff; but for me, handloading is just easier. It's a matter of priorities and the value of one's time. If 1/2MOA to 1MOA of accuracy out of a factory bolt gun at 100yd and 1MOA to 2MOA at 1000yd are good enough for you, I'll tell you it's certainly attainable with SAAMI chambers. If you demand more, we are on different sides of the divide.

Greg

 

[former naval person]

Re: Runout tolerances

Just don't close it down "correctly"...what is happening, in my experience, the expander ball upon withdrawal is canting the case neck. Let it float. Put a tiny "O" ring in between the lockring and the die head. It will let the "expander" ball float enough to help center the case and die. It isn't match grade stuff, but will eliminate a lot of the off center problems. JMHO

 

[MitchAlsup]

Re: Runout tolerances

I never found runout below 0.003 to improve accuracy. That is runout from 0.000 through 0.003 shoot about the same in my guns.

No question that by 0.005 the ammo is less than match grade.

 

[FNARSHOOTER]

Re: Runout tolerances

I am gearing up to load for my FNAR will neck turning be any good for a gas gun or am I wasteing my time?

 

[Victor N TN]

Re: Runout tolerances

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Scot</div><div class="ubbcode-body">I am gearing up to load for my FNAR will neck turning be any good for a gas gun or am I wasteing my time? </div></div>

I have turned case necks on over a thousand cases. Unless I had a tight "turn only" chamber or brass that was of poor quality and had to have the case wall evened out, I wouldn't be turning the necks.

Like stated above. If you have a sloppy factory chamber, you're fighting a loosing battle.

 

[Supersubes]

Re: Runout tolerances

Redding also makes floating carbide buttons for their dies. Truthfully though, if your getting results on target dont sweat it. You didn't mention how your gun was shooting(I may have missed that).

 

[bosulli]

Re: Runout tolerances

Question RE: SAAMI\factory chambers - the chamber on the AR 223 was made my Compass Lake Engineering. Would you consider that a SAAMI spec chamber? I am sure its not BR, but slightly, better than factory.

"How are they shooting" Both the 223 and 300wm are 1 moa, but lack consistency. Some days tack driver and some days too many flyers.

My goal is too shoot the 300wm at a 1000yds, and the 223 at 600. I read an article on 6mmBR about neck turning. It's point was that to shoot long range (1000yds), having small velocity spreads was important. That making all the cases the same was key, and one step was neck turning in order to have consistent neck tension. At the time I was about to have a 6mmBRX barrel made (AR platform), and I was going to have to form the brass and turn necks. I decided, I would work on getting the 300wm up to the task of long range instead of investing in the 6mmBRX.

So why I am I neck turning? I believe its to get more consistent velocity spreads. At the same time, trying to make more concentric loads. I like to reload. I like to figure out how to make better loads, and refine that skill.

I have never shot at over 300 yds. Shooting at 300yds is rare. I shoot at 100-200 yds regulary (twice a month). But its my long term goal to shoot precision long range. So, I am not sure of the road to go down to get there. I just read posts and articles on these sites, and go down roads that look like they should take me there.

Why AR platform? I realize that AR's are not as good as bolt guns. I like bolt guns. I dream of having a GAP or similar. I used to think AR's were a joke. I shot a friends AR. Took it apart, and put it back together. I started read about them on the internet. I like the idea that you design and put together your own gun. I like the history of the AR, and that they are actually used by the milatary (SASS & SDM). The AR platform allows me to tinker with my gun. I would find it rewarding to build a 600yd capable AR, make my own loads, and use it sniper competition.