Concentricity - setting up dies - runout

[Trickymissfit]

"...motor oil for sizing?"

I've been reloading for well over four decades. I've used most commercial case lubes and find that most are sufficent. I've experimented with a lot of alternates; some work well, some work moderately well, some are prone to letting cases stick.

Given that a good lube will pervent stuck cases, be easy to apply AND remove, be harmless to powder and primers and be low cost, there are several that work very well; motor oils are not among them. Even the most pricey case lubes are cheep in the quanities we use so attemps to 'save money' with them seems pointless. Well, except the expensive spray-on types, which I find pointless anyway.

IMHO, the best of case lubes are soaps like the RCBS/Lee water solubles, or soft waxes like Imperial/Unique and equivilent alternates such as Kiwi Mink Oil and Sno-Proof boot treatments. Not only are they all great sizing lubes but they are harmless and easy to remove from both cases and fingers...and are plenty cheap enough.

I learned about Royal Purple from a couple well known benchrest shooters. As I said, I have not had the time to test it. I mostly use Imperial die wax for full length sizing. Tried the spay can stuff, but didn't like it. I neck size with powdered graphite only. I've also seen guys clean barrels with Marvels and Mercury Outboard engine cleaner, and know at least one guy that cleans his cases with the stuff
gary

 

[dig]

Update - The H&H Concentricity Gage showed up a few days ago. This is a very well thought out tool. I have been using it on 375 and 300 wby cases. The good news is my run-out has been fine .003 or so. This tool is very easy to use and gives very accurate readings with no wobble, you may also measure case neck thickness. Great tool, good price, I would highly recommend this. Concentricity Gauge

 

[Bart B]

This tool is very easy to use and gives very accurate readings with no wobble.....

I don't quite understand how there'll be no wobble with reading as much as .003 inch. Runout readings aren't constant.

Nor do I see how it can be "The only gauge that reads accurately." as claimed in the web page on it. There are others that measure just as accurate.

 

[dig]

Well everyone makes claims, welcome to the 21st century and advertising/marketing. Thank God for it, part of living in America and having so many choices and free market and entrepreneurs like this company trying to build a better mouse trap! The one bearing point on the case and the spring holding it securely makes a difference from two bearing points that would measure possible differences in the case, reading case ie. wobble. I have not used a lot of other machines but the quality is excellent, its easy to use and better than the other device I tried. Service has been excellent, response to questions and even sending additional parts!

 

[Bart B]

The one bearing point on the case and the spring holding it securely makes a difference from two bearing points that would measure possible differences in the case, reading case ie. wobble.

At the back of the case body where it rides in the V block (which has two points where the case body touches), the normal out-of-round condition of the case at that point will cause wobbly readings even if the case neck and bullet are in perfect alignment and straight with the case body axis. 'Tain't no such thing as a perfectly round case.

The other problem with this type of cartridge spinner is anytime a rimless bottleneck case neck's not perfectly aligned with the case shoulder, the bullet will end up off center in the barrel's throat when the case shoulder centers in the chamber shoulder. Same thing with belted bottleneck cases that have been resized such that the case headspaces on its shoulder when fired instead of the belt.

The above aside, that cartridge spinner looks pretty good. A couple thousandths runout won't be any problem anyway.

 

[Mikecr]

Whoa, whoa,
Dig you've missed alot in these recent threads about this.
For one, there is really no difference between the H&H and Hornady.
And if you read as much as 2-3thou using either, you've got way more RUNOUT than that..

You are wasting your time & money,, AGAIN!!

 

[boomtube]

There is ONE machined surface on a bottleneck case; the extractor groove. It's not always perfectly centered but it is always a smooth surface and the potential for error due to any small offset is meaningless. My shop made concentricity gage has a narrow V-block for the groove and a bullet nose guide quite simular to the H&H. I have to roll the cartridges with my finger but that's fine with me. I do NOT have any thing to push a bullet straighter; don't want to chance deforming a thin jacketed varmint bullet out of round.

I hope everyone using such gages knows that the dial indicator gage, set up as it's shown in the H&H link, will read what's called TIR (Total Indicated Runout). TIR is twice the actual non-concentricty because it sees the same off-set as both high and low points from 180 degrees apart. Meaning a TIR of 2 thou is only 1 thou of non-concentricity... and that's really GOOD!

 

[dig]

Boomtube, good advice again. So if I am getting a hight to low reading of .0035 that would equate to 00175 in non-concentricity/runout? Very acceptable. On another note I am getting less non-concentricity with the SMK's I loaded in the same case and prep work as the Bergers in the same weight. Anyone else see this.

 

[boomtube]

"..if I am getting a hight to low reading of .0035 that would equate to 00175 in non-concentricity/runout? Very acceptable."

Correct, both counts.

 

[Mikecr]

But runout and concentricity are two different things.
Concentricity is referenced ONLY to centerline, with a quality described as hi/lo eccentricity from that centerline. With this, your DEVIATION(eccentricity) might be assumed as half the total indicated.
None of this applies to runout really.

The deviations causing runout, are a sum of ALL deviations, with possibly few if any of which relating to a centerline. TIR is just that. The total of it..
It's NOT eccentricity.

A loaded case can be perfectly concentric and still have plenty of runout from case thickness variance, or banana shaped cases, or casehead squareness, or bad seating(with adjustment}. All combining in abstract ways.
A loaded case that is perfectly STRAIGHT will be both concentric AND lowest in runout.

What is straight?
Straight means you could carefully place a low clearance chamber over a loaded round setting on glass, shine a light down the bore, and see the light all the way around the case, from the bottom.
But a loaded case that is declared concentric, yet not measured as straight, would likely fail this test. Very badly..

Then, you've got all the masking in measurement position going on with H&H type tools.
Here we go again,,
Picture a rigid jump rope(your banana case). If you care to see this deviation, and fix your processes to produce straight ammo, would you really chose to indicate nearest one end of the jump rope(it's fulcrum)? Or would you pick the middle?
You know there will be only a fraction of the actual deviation seen nearest a pinned/stationary end, right? Afterall, it's fixed in position very near that point.

With a v-block method, the center of the jump rope, and one end, are fixed. The deviation is then seen in it's entirety on the other free end.
That jump rope was always concentric. But it was never straight until measured so off a v-block.
That's an important difference.

If you've got 3.5thou deviation with an H&H, you've got seriously horrible runout.

 

[Bart B]

What is straight?

Straight means you could carefully place a low clearance chamber over a loaded round setting on glass, shine a light down the bore, and see the light all the way around the case, from the bottom.

Too bad both belted and rimless bottleneck cartridges don't fit the chamber that way when they're fired. Crooked, straight, or whatever shape cases there are; it doesn't happen.

 

[mo]

Hard to argue with Mikecr on this subject! I can tell the H@H gauge is built really well. I have one. Mike is right about how it operates, if the H@H shows .001 on the gauge you can turn around and measure it on a Sinclair and it will have at least .004 if not more. My conclusion is I wasted my money on the H@H.
Now I just load and shoot! To hell with the gauges! Wind reading is my biggest factor! I can't tell the difference between a .001 and .004.

 

[Bart B]

To hell with the gauges! Wind reading is my biggest factor! I can't tell the difference between a .001 and .004.

When testing my last new .30 -.338 barrel on my 1000-yard Win. 70 target rifle, I loaded two sets of ammo; 15 rounds with new cases (.300 Win. Mag. cases run through a .30-.338 FL die) and 15 with once fired cases full length double-sized ones. New ones had Sierra 200 HPMK's and the resized ones had 190 HPMK's; both had bullet runout up to 3 thousandths as measured with the case body right in front of the belt in a V block and a nylon washer mid point on the shoulder.

Both 15-shot test groups at 1000 yards were about 6 inches. All were fired alternating bullet weights in one 30-shot test to see how accuracy would be affected by barrel heat and fouling for a 30 shot string. The 200's group center was about 4 inches below the 190's as it used 1 grain less 4350 powder than the 190's.

I don't think bullet runout's all it's cranked (bent?) up to be. Same for barrel heat and fouling; not an issue with proper stress relieving of barrel steel and square-faced receivers fitting the barrel tenon shoulder evenly all the way around.

 

[Mikecr]

MO, I've also had both tools on the bench(and others). Sinclair V-Block(bearing) won.
It's refreshing to hear someone else concede that something they bought(especially if expensive) ISN"T perfect in every regard.
Most won't