- March 10, 2016 at 11:43 am #25734Kevin SParticipant
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I want to make a case run out gauge for loaded rounds. I have seen on Youtube. That some devices hold the case by nose of the bullet and the base of the cartridge. And I have seen other devices that support the base of the cartridge and just behind the shoulder. Is there any way better or worse for checking for runout?
After the cartridge is loaded. Is there any way of decreasing the amount of run out the loaded round has. Or do you have to live with whatever out of alignment there is.
There is no way I can afford one of the high end super duper bullet seating dies. Are any of the over the counter seat dies that perform to a higher quality in seating bullets straighter?
- March 10, 2016 at 2:23 pm #25736ArtfulParticipant
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For cast boolit seating the improved neck expansion M type die will improve boolit seating. The simplest way I know of is get some plate glass or other known flat surface and just roll the cartridge across it and use your Mark 1 eyeball to watch the bullet. If it is not concentric then it will be going up and down on the tip.
- March 10, 2016 at 3:35 pm #25740RegParticipant
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The RCBS unit will tell you a lot about the TIR and many other things about your ammo and cases. Only problem I have found with it is that on the smaller rounds sometimes your fingers get in the way but I think this would be a problem with any of the case checking tools out there.
TIR is important to accuracy.
One thing that helps is what you use for seating. The M dies help greatly also using a 20 degree chamfering tool helps with cast bullets. Make that chamfer deep.
I use a lot of the old “straight line ” type seating dies, these are very accurate and L. E. Wilson makes them for many calibers but be for warned, they are pricey but sometimes can be found used. If you have a chambering reamer and lathe you can easily make your own.
Have never used on but I understand there is a Vickers seating die out there that really works well but don’t know if they are even still available.
- March 11, 2016 at 2:27 pm #25769
In my opinion cartridge runout or CRO starts with the fired brass. If your fired brass is not concentric, then you need to know about it so you know what to look for when checking loaded cartridges.
Then you progress to measuring your brass as it leaves your dies. Did something change? Hmmmm. That’s going to happen in reverse order when the trigger breaks you know.
Then you measure bullets that have just started to be seated by your dies. The start is the key. If your dies are such that they start the bullet in a crooked manner then crush them into a more aligned condition, understand that the bullets are going to try to leave the brass in exactly reverse order from the way they were seated.
Then you measure the concentricity of your loaded ammunition. If you did as I suggest above, if it is wrong, then you know why, and if it’s right, you know why, and that’s what it’s all about.
You mention straightening the cartridges after they have been loaded. That is a practice used by people who put electricians tape over their check engine light IMHO. Remember that whatever you do to your ammo in the loading process is more or less going to undo itself in reverse order when you fire that piece of ammunition.
So, if you are looking at your loaded ammunition, and you’re saying you really want it all to be concentric on the gauge, and you think that the way to fix it is to just BEND your ammunition to make it appear to be straight, you will have ammunition that starts out concentric but quickly acts like the crummy stuff that it is when the powder charge blooms and the bullet deploys. Lets be smarter about this. You really want ammunition that gets more accurate as it is fired or at least holds what you’ve got right? OK, so be smart and don’t change the evidence to make yourself feel good about what actually happened in your dies. Change your reloading process to make it so you head innacuracy off at the pass. This is entirely what my “Consistency applied” article is all about and it reflects the attitude that permeates every bit of the shooting sports and separates the men from the boys on the fireing line as it were. You can apply this philosophy to anything of precision, and I recommend you do.
However, the biggest part of taking good measurements is doing it with fixtureing that allows you to establish firm datum lines and points. Sounds real complex, but the fact is, your measurements are only as good as the fixturing that is being used to hold the dad burned thing you are trying to measure! This is why tooling experts insist on gauge blocks and surface plates that are flat and parallel within millionths of an inch.
In this case (pun intended) we need to have a way to establish repeatable points of reference on a piece of brass tubing that was formed to shape under high pressure, but was easier to form in some places than in others.
There are many gauges on the market. Some use solid contact points, and some use roller bearings, but in my opinion the most important feature to have is adjustable contact points. You need to be able to measure the concentricity of your cartridge in relation to certain points located from the case mouth to the rim, and obviously, you are not able to achieve greater accuracy with loaded ammunition than you are with empty brass measured in the same way, so check what you’re doing and don’t be foolish about this. If your fixturing is not adjustable, then you are unable to measure anything unless you’re using brand new Lapua brass that has never been fired.
You also need an adjustable stop.
Many people feel that a test indicator is some sort of a little magic wand, and when it reads zero when you twink something with it, that thing is magic. There’s certainly nothing wrong with an indicator that reads zero as long as it’s touching the cartridge and is not bottomed out, however, it’s telling you what you have to the specific datum lines that you have established and nothing else. Remember that.
An indicator for something like this needs to be subtended to .001 graduations at least. Understand that this means you are only accurate to .001 and you cannot really trust the readings less than that. I prefer an indicator that is graduated to .00005 with a total sweep of only .008. This is very difficult for many people to work with.
- March 15, 2016 at 12:04 am #25886dragon813gtParticipant
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If it helps. I’ve found Lee dies to load rounds w/ minimal runout. I have a Forster Co-Ax Case and Cartridge Inspector. The merits of this unit versus the others is a debate that will never end. I’ve found it to work perfectly for me needs. This is it: http://www.forsterproducts.com/product-category/case-and-cartridge-inspector/
Like I said, Lee dies gave acceptable results for me. I have a few overlaps in dies and checked them against each other. If you truly want ultimate benchrest accuracy than you should be using benchrest tools. A press and dies is usually not what one would be using.
- March 23, 2016 at 11:20 pm #26253
Why not just put the case in a good chuck and spin at a reasonable RPM? Look for runout with a magnifier or just use your ‘calibrated’ finger pressure. If you can see or feel it it’s a problem.
Actually I’d like Goodsteel to run some cast boolit bases in his GC uniforming test to see how flat and true the base is on a normal cast boolit – how true is the sprue cut? For those of us that only have hand tools.Refer to PC accuracy target I posted, ring around POA. Is the base not flat enough or is the coated base making it that way?
- March 23, 2016 at 11:39 pm #26255
popper;n4783 wrote: Why not just put the case in a good chuck and spin at a reasonable RPM? Look for runout with a magnifier or just use your ‘calibrated’ finger pressure. If you can see or feel it it’s a problem.
Because if you don’t measure anything, you are unable to follow the scientific method of “change one thing, measure, repeat, compare, repeat” to identify what you are doing that is causing error, learn from it, and correct it. Those who do not follow these principles spend their lives confused about where they are going, confused about where they’ve been, and totally unsure of how they got where they are. Moreover, when someone ignores scientific method entirely, and refuses to measure anything, when they finally do find the magic combination by pure dumb luck, they can’t hold onto it because they do not know how they came into possession of it in the first place.
That’s why we measure and compare to a repeatable standard at all times.
- March 24, 2016 at 3:17 pm #26277
Agree with your statement but for those of us wanting to check without deep pockets for another tool – as generally applied to bottleneck rifle cases, put neck in chuck. If you have a long boolit with exposed drive band – put it in the chuck. Length of case will magnify errors. If your die are creating the problem it will show. If loading process, solve the problem. Obviously the check bearings have to be good if yo use the touch method.
- March 24, 2016 at 5:35 pm #26289
Not to argue, but I have to ask, in a world where 8lb of powder costs nearly $200, and starting price for a “middle of the road” new rifle is $600, and 1000 30 caliber bullets cost nearly $300, I have to wonder when someone who has all of these things claims not to have pockets deep enough to buy some simple measurement tools to make it so they get the most out of the previously mentioned investment?
It’s far more likely that someone places far more importance on making bang noises than on actually demonstrating excellent accuracy.
The tools are not horribly expensive compared to what we spend on the entry fee, and if you don’t think it’s important, then don’t waste time pretending to measure something when you’re not really doing anything but trying to satisfy yourself that you nodded at it.
The chuck only works if the lathe has less than .0005 TIR itself, and I would submit to you that what the chuck is attached to is astronomically more expensive than a simple TIR gauge, and it does not give you the ability to check from the middle of the case (the fireformed section) and move the points to specific places that are controlled by your dies so that your measurements actually mean something. Just go ahead and measure some fired brass using your method (heck, measure some NIB brass) and see just how bad it is. The rims are out of concentricity with the body and the neck unless you are using Norma Match, and if you’re holding onto that part, you’ve got nothing. Everything sticking out is going to be running amuck.
Same with holding the bullet. Unless you have a collet that matches the bullet diameter exactly, and you have proven that you can put bullets in without a loaded casing attached to the same depth and achieve PERFECT TIR on the base, you’re wasting your time.
Meanwhile, placing precision bearing contacts directly against the case body and measuring the TIR of the ogive, and neck doesn’t lie, and needs no special attention. What you see is what you get. Then put one contact on the neck, and the other in the middle of the body and measure the TIR of the ogive as compared to the shoulder of the cartridge, you’ve got a very real idea in thousandths of an inch, exactly how concentric your ammo is.
- March 25, 2016 at 2:05 am #26310W.R.BuchananParticipant
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I have never worried about runout on my reloads simply because they are all fired at things that are so big it really doesn’t matter. Also I am a Machinist/Toolmaker and can generally look at something a determine if it is catiwhompus . This is known at the “Calibrated Eyeball.”
However my Reloading Tools consist of the best stuff there is so deviations from zero are going to be minimal because the dies I use don’t create a problem in the first place, and I don’t make it worse in the second by trying to fix something that I can’t really fix. The only real thing you can do to correct excessive bullet runout is to disassemble the round and toss the case in the recycle bin. It’s not worth the time to try to fix the case unless there are no more of them available. I have done it sometimes just to prove I could but don’t make a habit of it.
This also could have been caused by and out of round chamber in the gun so no amount of tweaking is going to fix that because the gun is making every round junk as soon as it’s fired. Obviously this is a gun problem and not a ammo problem.
I can measure runout on a bullet by using a vee block and an indicator because I have the tools in my shop to do it. Since there is little you can do to change a loaded round about all you are confirming is whether or not your dies are junk. Very few reloading dies by any known manufacturer made in the last 10-15 years will be bad. All this stuff is made on automated machinery and tolerances are kept to a minimum and well below the status of junk. Prior to that there were issues from time to time so if precision is what you are looking for then I suggest you buy new dies instead of some old stuff off Ebay that is listed as “Vintage.” And Lee dies are just as good a Redding dies IMHO! Seen more crap from Redding and none from Lee.
BUT!!! Back to the inspection aspect of this conversation,,,
No matter how you check your work if you can’t get your measurements to repeat at least 3 times you probably haven’t gotten a good measurement in the first place, which in fact means you’ve got nothing,,,and therein lies the Rub.
You are only as good as your ability to use the tools you have. So in the beginning you need good tools then you need learn how to use them effectively. You also need to use the proper tools for any given job.
I get a kick out of guys talking about measuring boolits to a half thou with calipers. I’ve been doing it for 40 years and I can’t get good enough measurements with calipers to even bet a finish cut with a Hardinge Lathe on. I will use a Micrometer for the last measurement everytime if the part is critical enough to warrant close inspection..
If I am boring a hole in a part that is critical I will use calipers to get in the ball park,(within .010) Then telescoping gages and micrometers to get where I need to go. But I also will measure that hole 3-4 times to make sure the readings repeat, simply because half the time they don’t. If they don’t I don’t proceed until they do.
If you don’t know exactly where you are at,,, it is impossible to get where you want to go. I’ve also heard, “you can’t get there from here.”
So you can see that,,, If I,,,with 40 years experience, don’t trust myself until I check myself thoroughly,,, Then maybe it would be a good idea for you with less experience to check yourself as well
And in order to do that you have to first learn how to do it. There are many books available on the subject of Loading Precision Ammunition and Using Measuring Tools. I would suggest obtaining one or two, and reading them several times so that you really understand what is being taught.
Believe me when I say ” Nobody gets it all the first time thru !”.. Certainty only comes from many times over a given subject. That’s what experience is,,, Many times over a given subject.!
This applies to more than just reloading ammo.
Tim also talks about consistency and this part of that.
- March 25, 2016 at 4:54 am #26324
Hell of a post Randy. Kinda cringed when you threw Redding under the buss, but I’ll get over it. Other than that, you hit the nail right on the head. Couldn’t agree more.
- March 26, 2016 at 9:11 pm #26420dragon813gtParticipant
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I submit to you a way to fix runout: http://www.trutool-equipment.com
Personally I think you will just make things worse because there no way to precisely line up the case and move what part needs to be moved. I’ve seen a few different versions of this type of tool. I do wonder how many they sell.
- March 26, 2016 at 11:00 pm #26427Wright ArmsParticipant
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I believe ‘fixing’ cartridge run-out is akin to ‘fixing’ rust. It’s gonna come back. It’s just a matter of when and where. I thought the entire run-out measuring exercise was to find the source and correct it if possible. Might be as simple as a new die or better brass. If it’s a maxi-size chamber, then you’ll have to learn to live with it or it’s time for barrel work, me thinks. But ‘fixing’ loaded cartridge run-out? No, I don’t buy that approach.
- March 27, 2016 at 5:13 pm #26467
No problem with really good measuring tools. It’s cost vs need. I’ve used >$100K measuring equip. in the past – but I didn’t have to pay for it. I don’t buy 8# jugs as I’d not live to use it all. To Kevin’s post, You use a good tool to check your die – if they are off, get better ones. Same for chamber checking. If checking loaded ammo for competition, assuming everything else is OK, toss the bad brass and fix your technique. If you have one of those good TIR setups, store in in a vacuum seal bag.
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