Weird Issue with Run out

Aldon

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Location
Malta NY
Weird because I am trying to understand what the data is telling me....

I started reloading again about 1-2 years ago. I had reloaded a little with the stepfather when I was younger but that had been a long while before and all knowledge had evaporated.

I initially read through many of the posts on LRH and a few other sites. and settled on the methodology below based on what I had learned. Went out and aquired the equipment and got busy....Mostly successful thus far.

I decided to go to the next level in quality and purchased a Sinclair Concentricity Guage. I had trusted that using the Collet Neck dies by Lee that I would be getting pretty good loads.

-now to recent issue- Upon setting up to load however I found my concentrity to be worse than I would have conceivably thought.

.

Steps I tend to use most of the time:

I use Lee Universal Decapper to deprime.

Clean Brass. Walnut Media in Tumbler with Flitz.

As Necessary, indicated by the LNL Guage, I use Full Length Forster Die to bump shoulder. (With deprime/neck sizing rod Removed)

I then run the brass through Lee Collet Die.

Trim if necessary. I sometimes go through and Collet Size again at this point.

Prime Brass using the Forster press as I like the consistent depth control and I am not usually in a rush. It actually goes pretty fast.

Load powder and then seat bullets using Forster Bench Rest Seater or Micrometer Seater depending on what I have for that caliber. <just an FYI..i personally like the Forster BR Seater Dies better than the Micrometer dies. I did pick up a Redding Micrometer to see if I like them better than Forster but I may just sell all of my micrometer dies and go with BR Seaters>

Double Check everything at every step of the way and go.....

I now have additional step and check

I recently purchased the Sinclair Concentricity guage and I finally decided to load some rounds in 30-06 for a new Browning BAR I acquired(long story).

When I checked concentricity I was way out of whack.

I was getting on average .007 run out or .014 total indicated run out.

I have checked everything and adjusted dies and press etc...

I get tightest or best run out using the Full length Sizing Die completely sizing necks and then utilizing Benchrest Seater I get runout of .0015 and total indicated of .003.

It appears as if my Collet Die is the cause but it is hard to believe because outside neck measurements are on average very good and match close to the Full Length brass prep.

But the end result is telling.

Has anyone experienced similar or have an idea I have not thought of that might be causing the run out?

I have not yet tried any other calibers yet. This was for 30-06. I initially thought that it might point to a need to anneal the brass but I had some new Lapua on the bench and was able to reproduce the same results.

It seems the more I learn about reloading the more equipment that I need and the more I know I dont kjnow:)
 
Have you checked the brass prior to loading?
I would check your new brass, once fired (before you do anything to them, after sizing, and then after loading.
You need to determine where in your process the runout is being introduced. You can also check the bullets by themselves.

Where on the case and bullet do you place the probe?

Hope this helps a little, do one thing at a time and check before and after each step.

Good luck,
Ray
 
Thanks Ray.

I have checked the Brass after each step as you mentioned. Also before loading.

The introduction of the issue seemed to be after the lee Collet Die step. But after this step, brass looks good, then upon seating everything looks off,

Perhaps it is the bullets but then I would have no clue why less Run Out using Full Length sizing on the brass.

I am thinking it may have something to due with the tension of the neck.....and it could be that the seater is teh issue and the full tension of full length sizing masks the root cause.
 
.002 runout in a sized empty case will alot of times give .004 or double the runout by time we load it.

As Padd says, check during the process to determine the true culprit. I check mine for neck thickness variance and runout prior to resizeing, and can eliminate some runout that way.

Some runout can also be eliminated by resizing and seating in a two stage process (partially size/seat with one partial stroke, rotate case a 1/4 to 1/2 revolution and complete the size/seat with another full stroke.

You mentioned removing the expander ball on the de-capping rod. Sometimes it's better to use the expander, because if you don't the neck tension is too much to seat a bullet as straight as possible. Really forcing the bullet into the neck can cause alot of runout all by itself. Flat base bullets especially.

I am not familiar with the Lee Collet die you're using, I tried some lee dies for my 220 Swift about 20 years ago and wasn't at all impressed. I quit using them and never went back.

Disregard some of this, I see you were posting at the same time I was typing.
 
Weird because I am trying to understand what the data is telling me....

I started reloading again about 1-2 years ago. I had reloaded a little with the stepfather when I was younger but that had been a long while before and all knowledge had evaporated.

I initially read through many of the posts on LRH and a few other sites. and settled on the methodology below based on what I had learned. Went out and aquired the equipment and got busy....Mostly successful thus far.

I decided to go to the next level in quality and purchased a Sinclair Concentricity Guage. I had trusted that using the Collet Neck dies by Lee that I would be getting pretty good loads.

-now to recent issue- Upon setting up to load however I found my concentrity to be worse than I would have conceivably thought.

.

Steps I tend to use most of the time:

I use Lee Universal Decapper to deprime.

Clean Brass. Walnut Media in Tumbler with Flitz.

As Necessary, indicated by the LNL Guage, I use Full Length Forster Die to bump shoulder. (With deprime/neck sizing rod Removed)

I then run the brass through Lee Collet Die.

Trim if necessary. I sometimes go through and Collet Size again at this point.

Prime Brass using the Forster press as I like the consistent depth control and I am not usually in a rush. It actually goes pretty fast.

Load powder and then seat bullets using Forster Bench Rest Seater or Micrometer Seater depending on what I have for that caliber. <just an FYI..i personally like the Forster BR Seater Dies better than the Micrometer dies. I did pick up a Redding Micrometer to see if I like them better than Forster but I may just sell all of my micrometer dies and go with BR Seaters>

Double Check everything at every step of the way and go.....

I now have additional step and check

I recently purchased the Sinclair Concentricity guage and I finally decided to load some rounds in 30-06 for a new Browning BAR I acquired(long story).

When I checked concentricity I was way out of whack.

I was getting on average .007 run out or .014 total indicated run out.

I have checked everything and adjusted dies and press etc...

I get tightest or best run out using the Full length Sizing Die completely sizing necks and then utilizing Benchrest Seater I get runout of .0015 and total indicated of .003.

It appears as if my Collet Die is the cause but it is hard to believe because outside neck measurements are on average very good and match close to the Full Length brass prep.

But the end result is telling.

Has anyone experienced similar or have an idea I have not thought of that might be causing the run out?

I have not yet tried any other calibers yet. This was for 30-06. I initially thought that it might point to a need to anneal the brass but I had some new Lapua on the bench and was able to reproduce the same results.

It seems the more I learn about reloading the more equipment that I need and the more I know I dont kjnow:)

do two things:
1. sell the collet die and never regret it.
2. on your full length die, put an O ring under the top jam nut just for the stem. You want it to be able to follow the neck wall on the way out without be ridgidly in place

might try this:

1. buy a combination stone that is fairly smooth.
(a) stone the bolster plate of the press to remove any hickeys
(b) stone the top and bottom side of the jaws to make sure they are good and
flat
(c) adjust the 1/4-28 screw that opens the jaws so the the jaws are a little
loose at both ends of the stroke (this makes it easier for the case head to
float during the sizing stroke). I run mine just tight enough to hold onto the
case rim when I pull the case from the die
(d) Stone the base of the case to remove dings left by the extractor (not
much)
gary
 
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You didn't say which Sinclair Concentricity gage, or where you are measuring. It helps to take this to the very basics. Is it the bearing block w/indicator? Are you measuring off the bullet noses or necks?
Have you measured this brass thickness variance?

I don't know why you FL size necks, or followup with an additional neck sizing, or seat bullets without a neck expansion to proper size. With this, you are down sizing too much/too often, and then partially upsizing the necks -with your bullets.
Bullets are not made for neck sizing..

Good questions though. We'll figure it out.
 
The Sinclair unit is #09-150. It is dial faced or Analog vs digital. I like the idea of watching the needle sway vs digital numbers....more intuitive in my mind. It is the bearing block with indicator i believe. 4 false round rests that appear to be bearing balls but are only really rests.

The location I chose to measure is nearer the point, basically approximately where the lands would engage.

I have the ability to measure necks with digital Tube micrometer and stand, however I have not yet turned necks nor do I have the equipment to do so yet. (next on the list).

I have no tight necked rifles and thinking that any error would be pushed to the exterior of the necks, I left this as the last priority, knowing that it will eventually need to be tackled. So I measured the necks and the readings i get are similar to this case:4 measurements around diameter- .0127, .0147, .0137, .0138....one of the more evenly distributed is .01470, .0145, .0145, 0.143...

I understand that the tensions and accuracy are affected by having the tension of the necks uneven, but for now, that is good enough for a hunting round. But having the concentricity as far off as it was seems to me to be an immediate concern.

I use the full length sizer to bump the necks when I use the full length die to bump and that is due to only needing to do so recently.

The Redding Bump dies are being acquired as they become needed and funds allow. Only so much in the proverbial piggy bank and it appears they will need to be prioritized a bit higher.

As to the seating bullets without proper sizing I only just realized(feeling stupid publicly..sigh) that is what I had done by seating after sizing without the expander. Agreed, not proper methodology. But it did yield the only accuracy run out wise. Fear not, there is no powder and it was done experimentally as I was trying to troubleshoot the root cause.

Thanks for any ideas to try. May not get back to them fully until next weekend though.
 
There is an excellent article on the Redding Reloading equipment web site on this very subject. Their consensus is that run out is most of the time caused by brass being thicker on one side all the way from the head to the neck. The only thing you can do with this brass is to throw it away if the run out is more than say.005. Neck turning is a useless procedure, very seldom is it the die or any other piece of equipment you are using. I stopped pulling my hair out about run out after reading the info on the Redding website. Now I just sort my brass according to run out. The very good stuff (.003 or less) I use for hunting. Sometimes I only find 10 good pieces in a 50 round packet.There are some that say partially seating the bullet then turn it 180 degrees in the seater and finish seating will sometimes correct run out. I have never ever found that to work for me. I have been reloading for 5 years and I reload for the following calibers. 22/250, 30/06 Springfield, 30/30 Winchester, 300 Weatherby, 338.378 Weatherby. 375 H&H, 308 Norma, and 300WSM, 50cal flintlock and 50cal Hawken.

Cheers & Tighter Groups: Eaglesnester
 
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Thanks for the info on the Redding Article.

Interesting info,,,,


I think i need to start form scratch and see if I have similar issues using new brass.

I have some new Lapua of which I snagged one piece to try and duplicate the problem but i need to start over as a couple above mentioned and pay particular attention through each step to see if I can improve run out.I may have induced it and caused a red herring trail,,,,

My gut tells me that brass and work hardening are the root cause.....just hard for me to prove out not having the stuff to anneal brass at this point.

I still like the idea of uniforming all the necks for given lot.....so am probably going to pull trigger on a neckl turner of some sort before too long as well......
 
Thanks for the direction Gary.

These sound like good ideas.

Regards, Aldon

that's something that most guys using Forster sizers do. Sometimes you'll pick up a thousandth of an inch, and other times it's only a couple tenths. If you have a bump or a burr on the case head or where it contacts the bolster plate on the press it triangulates into significant numbers. Still if you seeing .0015" TIR you doing something right.

If your using the dial indicator that came with the Sinclair gauge you maybe better or worse than your readings show. That indicator has 10% lag built into it! But is usable if you start you readings at the low point, and constantly gain in the reading. If the indicator starts in one place and goes plus, and then minus; the error comes to play. Try (borrow one) a wand type indicator to do a compairison check. Who knows you might be better than you thought! I often recommend to folks that they seek out a B&S Best Test or better yet an Interrapid with .0005" readings. These are zero lag indicators that will give you a much more accurate reading. One last thing to check is to see exactly what reading you are showing just ahead of the base of the case. If you are showing error, I suggest you mark the high spot and rotate the case 180 degrees. If the error stays put in the same spot, I'd send the gauge back for replacement (the error should rotate 180 degrees when you move the case 180 degrees). ( some folks as expected will not like reading this)
gary
 
You stated that you first use the Forster FL sizer w/o the expander. That will compress the neck.

Then you stated you ran it through the Lee Collet Neck Die. I think this is your problem because you are forcing the mandrell into the neck without any support around the neck. The case will bend to the path of least resistance when forcing the mandrel into the neck and there is no telling what you might end up with. In normal operation, when the expander is pulled up through the neck on the FL sizing die it has the side wall of the die to support and align the case. No support (forcing the mandrel into the neck) offers no control. Keep in mind the collet neck die is designed to compress an already expanded neck down against a mandrel, not the other way around. You should not use the collet neck die to expand the neck.

Use one die or the other but not both. In fact, I would suggest you do both dies (the Forster complete with expander ball) and compare the results.
 
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I think y'all are misunderstanding the concept of runout -vs- concentricity..
I know Sinclair merchandises Aldon's tool as a concentricity gage, but that is not at all what it is. It is a RUNOUT gage.

Runout cannot be automatically be declared as 1/2 of total indicated from given centerpoint. There is no centerpoint here.
It simply is what it is, until further defined.
Cartridge brass is not round, it's roundish. It's not straight, but somewhat straight. It's not uniform, but varies in thickness, and springs back into many possible forms.
The same holds for the chamber your brass formed in, and the barrel steel around it.
The runout you measure on your Sinclair amounts to the sum of these factors, and is not just +/- 180degs. No way to make that assumption..

The fact that runout is very hard to conceal from the Sinclair is what makes it such a useful tool for working all the bugs out in reloading. It just won't allow you to deny the fact that your loaded ammo is not straight,, Yet..

I respect your endeavor here Aldon. No doubt you're learning alot, and will soon be producing very good ammo. As mentioned(a Redding link), the best approach to reducing runout is to cut the head off the snake(culling brass by thickness variance).
Then, the lowest runout you'll ever measure is from brass still smoking from the chamber. Each and every single thing you do to brass from there, increases runout. So to manage truly low runout, means doing as little to the brass as possible.
And this is what anyone should strive to do.
 
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