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Howdo I measure brass concentricity

I'm new to reloading. I bought all new equipment and have been having a ball developing loads for my 222 . But as I get deeper and deeper into this hobby, I get more and more critical.
I have found that the bullet concentricity is not not very good and I don't know why. Reading other postings claim the problem is linked to good brass. I use anything I have left over from factory bought ammo. I use Hornady, Remington, Frontier and PPC. When I measure the run out, I get around . 003 TIR. measured at the ogive. I found that when pressing the bullet, if I rotate the case 90 degrees and seat the bullet twice, it helps.
Another item of concern is when I mount the brass in the Lyman lathe type OAL trimmer, there is slight interference with the mandrill and the inside diameter of the neck. I would think this would affect the diameter and affect the neck tension.
So how does one check the neck concentricity so I can improve the run out??
 
Before you get any farther with this, what sort of load have you been shooting, with what seating depth? Also what accuracy have you been getting? Has your action been bedded, trigger lightened? What are you shooting off of? Do you have any way to look at the wind between you and the target? Concentricity is important, but, relatively speaking the things that I mentioned are more important. When you are talking about taking concentricity below .003, and if you are trying to gain accuracy, it may be that there are other, more important areas that you need to work on first.
 
BoydAllen said:
Before you get any farther with this, what sort of load have you been shooting, with what seating depth? Also what accuracy have you been getting? Has your action been bedded, trigger lightened? What are you shooting off of? Do you have any way to look at the wind between you and the target? Concentricity is important, but, relatively speaking the things that I mentioned are more important. When you are talking about taking concentricity below .003, and if you are trying to gain accuracy, it may be that there are other, more important areas that you need to work on first.
+1
This is exactly what i was thinking but couldnt figure out how to type it without it being a mile long..IMO no sense in investing all this into a factory off the shelf huting rifle. More details about the rifle and shooters set up is needed to make a wise choice
 
If you are trying to improve case concentricity, make sure the cases are adequately lubed (but not over done) and take the expander mandrel out of the sizing die. To get necks where you need them I would suggest using either a bushing die that gets the ID of the neck exactly where you want it for the neck tension you desire without needing expansion or use a bushing that over-sizes the neck ever so slightly and use a Sinclair expander mandrel to get the ID right.
 
Triple Deuce: Just for your own peace of mind, load the brass with the worst runout identically with an equal number with the least runout, take them to the range and shoot for group size, side-by-side. Bet you will see very little, if any difference, especially at 100 yards, and doubt at 200 yards either.

Actually .003" of total indicated runout is not bad in my book, more than that and I would agree it would start to be a concern, but at the shorter distances that the 222 is capable of, I've never seen it as a problem.

I also believe in seating the bullets incrementally, seat 1/3, rotate case 120 degrees, seat 1/3, repeat for final seating. I'm also one who believes that occassional runout is caused by a piece of defective brass, otherwise all 20 would have equally bad runout, as opposed to the usual 1 or 2 rounds that I may get out of 20 loaded. Minimal, or no runout with 222 Lapua brass, just a little more with Winchester, but not enough for me to worry about.

Using the Sinclair dial indicator concentricity gauge to check for R/O.
 
Wondering what brand of dies you are using and your case prep routine? Maybe some of the top shooters could give some pointers that once they know your reloading equipment and process, could offer ideas. However as already stated, there might be other areas that would give better or more consistency of group size at this point, but low runout is always desirable for sure.
Best Wishes
 
Triple Deuce said:
....I use Hornady, Remington, Frontier and PPC.

Though I agree with what Boyd says, IMHO opinion the brass you list isn't exactly what I'd call the top quality available and could be adding to your headaches, along with what Boyd mentioned. Just my thoughts.
 
Gentlemen - I thank you for all the interest and helpfulness with my concentricity problem. Let me fill in the blanks to answer some of your questions.
1. I'm using Hornady "new Dimension" dies to full length size my brass and also Hornady dies with the slip sleeve design to press my bullets.
2. I'm shooting a Remington 722 rifle (stock) with a Weaver 4-16 Classic scope.
3. The load I'm working with is a 50 gr. Nosler ballistic tip, 23.5 gr. Benchmark powder. Remington 7 1/2 bench primer. Mostly Hornady once fired brass.
4. Right now if I shoot for load developement I'm shooting off a Caldwell Lead sled and getting about .5 MOA. at 100 yards.
5 . No pillars or glass bedding.

I am just striving to get the best out of the gun and the loads. I don't compete (yet) but maybe some day. When I roll a loaded cartridge across the table and I see the bullet tip wobbling like a bent Q stick, I know it can't be right.

Does these gages from Sinclair measure the inside diameter?
 
I tested the seater that you are using against an arbor press type, and the Hornady gave twice the runout. For that reason I do not think much of short sliding sleeves. There is another one out there that gave even worse results. If you do not want to go that way (arbor press), my friend speaks more highly of his Forster seater than another, more expensive brand that he also owns.
 
I dis assembled my Hornady depriming/sizing die last night and found the threaded rod for the neck sizing was bent. I have no idea when it happened. I am surprised it bent but all I can think of what might have happened was I stuck a case and possibly in the process of removing the case, I bent the threaded rod.
I'm going to find another brand of dies.
I thing this solved the issue. Thanks for the input everyone.
 
BoydAllen said:
I tested the seater that you are using against an arbor press type, and the Hornady gave twice the runout. For that reason I do not think much of short sliding sleeves. There is another one out there that gave even worse results. If you do not want to go that way (arbor press), my friend speaks more highly of his Forster seater than another, more expensive brand that he also owns.

If you had to choose between Forester or Redding seating die what would be your choice?
 
If you had the decapping stem adjusted too low, that could have bent it, if you pushed hard on the press handle. I have no problem with their sizers, but their seater is another matter. If you are looking for another brand, I suggest Forster. They will hone out the neck of the FL die, if you want, for a very reasonable charge. You could also go to a Wilson seater and arbor press.
 
raythemanroe said:
]

If you had to choose between Forester or Redding seating die what would be your choice?
I have both the Forester Ultra Micrometer Seater Die and the Redding Competition Seating Die in 6BR and to me they are both equal in performance. I originally had just the Redding but I got a super deal on the Forester from someone who no longer reloads. I loaded 50 rounds of the same load today, 25 in each brand die to once again compare them and the results were the same. I checked each of them on my Sinclair Concentricity Gauge with equally good and consistent results. I usually leave one die set up for one load and the other for a different load so I do not have to mess with the micrometer settings.

I know someone will bring up the fact that the Forester case is a better case than the Redding case and it is but not enough to be a deal breaker if buying one.
 
Did you check them from ogive to head for consistency? That is where my friend saw the difference, and it matters.
 
BoydAllen said:
Did you check them from ogive to head for consistency? That is where my friend saw the difference, and it matters.
All I have left are the 25 I seated with the Redding. I just measured them for you and 12 were right on, 8 were .001 low and 5 were .001 high. Tell me how those numbers look. I think the Forester numbers usually run about the same but I do not have the exact numbers to compare. Next time I reload some more with the Forester I will record the numbers for you.

I do like the larger micrometer top of the Forester and of course their box.
 
And the price? :) Your numbers look good. Do you feel much difference in seating force between individual rounds? A friend has started annealing and he got an improvement in consistency of seating feel and accuracy, in a couple of varmint caliber rifles that he does not turn necks for.
 
BoydAllen said:
And the price? :) Your numbers look good. Do you feel much difference in seating force between individual rounds? A friend has started annealing and he got an improvement in consistency of seating feel and accuracy, in a couple of varmint caliber rifles that he does not turn necks for.
I will have to pay more attention to the difference in seating force when I seat the bullets and let you know.

Looking at a 2012 Sinclair catalog, the Redding is $96.99 and the Forester is $71.95 so it looks like the Forester is a better deal. I bought my Redding as part of a 3 piece Type "S" Match Neck Die Set which includes the Type "S" Bushing Neck Die, a Body Die and the Competition Bullet Seater. That saved about $10 but would still be more expensive than the Forester.

Right now I am still happy with having both of them but I guess less money in my pocket.
 
I also have a 722 and noticed early on that when I extracted the fired case, the ejector spring was strong enough to push the case neck fairly hard against the side of the chamber and cause it to bend out of concentric right there. Some of this can be straightened out when resizing, but not nearly as nicely as if they come out straight to begin with. I finally lightened up the ejector spring but even removed the spring all together and the problem was solved, but now I shoot it as just a single shot, removing the fired cases by fingers each time. The 722 is a fine rifle but was not exactly designed to be a target rifle but a repeater. Due to the long neck of the .222 case, it is easily pushed out of concentric upon extraction. Hope this helps. Also would suggest Lapua or maybe Norma brass if you are going for top accuracy and maybe some VVN 133 powder, working up slowly to about 22.9 grains.
Best Wishes.
 

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