sizing die/neck tension/pressure/accuracy/whipped

S

speedgun

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Thanks for looking! I am at a loss as to what to do with my reloading technique. I think that my reloads have way too much neck tension. When I seat my bullets, it takes considerable pressure and there is a definite pop when the bullet goes into the neck. I always have the little shavings, and I think it is causing inconsistent groups.
It is not my intention to develop BR quality loads but I want to be better than this. I like to F/L resize all my loads, and try to be consistent in my neck chamfering and I have tried graphite as well as lubing the neck, but the resistance when seating a bullet is obviously excessive. This problem seems to exist throughout the range of calibers I load, and regardless of which brand of the two different sizing dies I have.
Initially, I thought it was due to growing neck thickness, and am ready to purchase neck turning equipment, but I have started just reloading with new cases and it hasn't helped.The majority of my reloading is .243, 25-06, and .270. Any insight would be greatly appreciated!
 
With a need to start somewhere you could start by measuring you neck ID and OD, calipers will give you a good enough estimate of what you have. Using a micrometer measure the expander ball(s) in your sizing die(s). You want everything to be uniform. If you have mixed lots of brass with differing neck thickness the neck tension or bullet hold will not be consistent. If you plan to get serious you will want a good ball micrometer to measure neck thickness and also make sure your neck thickness is concentric taking several measurements around the necks. Finally a good concentricity gauge is popular among the bench rest and serious target shooters.

Neck turning (or reaming) is generally reserved for chambers having a "tight neck". You can also look to the more expensive loading dies which have collets for getting neck tension down to a uniformity science. Just remember the importance of starting with uniform brass and good quality brass. Then also there is a matter of bullet quality and consistency. Everything needs to come together. Lousy non-uniform brass with top notch bullets won't work.

Ron
 
Buying Lapua, Norma, or Nosler brass will drastically reduce variances in case neck wall thickness. That should smooth out some of the neck tension variance.

I turned necks until I moved to Lapua and Norma. I rarely turn necks now.
 
Thank you for your response. Is my complaint about the excessive seating pressure,and the ever present shavings valid. I actually had my Forster seating die bullet seater crack. Of course I am concerned about concentricity, and I have considered a different type of sizing die, I just don't understand why even with new cases I have this problem.
 
I would start by measuring the expander plug. I would like to see a diameter of .002"-.003" smaller than bullet diameter. Calipers, by the nature of the jaws, won't give a real accurate ID measurement, but you can try because spring back may be happening. Also you can chamfer and/or flare slightly the case mouth. K.I.S.S. to start...
 
This may not be the whole answer to your issue, but do be sure to lightly chamfer the inside of the case mouths before first reloading and after every trimming, so that flat based bullets don't have to pop over the square inside of the mouth.
 
Thank you for your response. Is my complaint about the excessive seating pressure,and the ever present shavings valid. I actually had my Forster seating die bullet seater crack. Of course I am concerned about concentricity, and I have considered a different type of sizing die, I just don't understand why even with new cases I have this problem.
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If you are shaving copper jacket copper off bullets obviously something is not quite right. Have you measured anything which was suggested? Nobody here can see what you have going on. Measure your case mouth ID, measure your expander ball OD and measure the case neck thickness. A few basic measurements should reveal quite a bit as to the bullet fit and your neck tension or bullet hold.

Ron
 
I do not deal in neck tension because my necks do not have tension and then; even if I did have neck tension there is no reloader anywhere on any forum that has a gage that can measure tnesions. I know, it sound cool; "I use 14 tensions" or "I increased my tensions to 20 tensions".

There is not tool that measures tensions, there is interference fit and crush fit but there is no gage that measures tensions.

When it comes to seating a bullet into the neck of the case I have found alignment to be the most important. And there is the bevel and chamfer and the boat tailed bullet. I made a seater, I can not call it a die because it does not have a die body, it is a seater only. I do not know of a manufacture that makes a tool that aligns the neck of the case with the billet better. When seating 25 cal bullets I can use a recycling aluminum can crusher, bottle corker or bottle capper; it matters not, bullet seating is effortless.

F. Guffey
 
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same goes for the Gold Medal and competition seating dies. And then there are Hornady new Dimension dies without the opening in the side of the die body. Before that distributors of seating dies sold one that was called 'The universal', basically the reloader purchased one die body with different seateer plugs and guides. Today reloaders find the dies without makings and then start a new thread about wanting more information.

F. Guffey
 
This may not be the whole answer to your issue, but do be sure to lightly chamfer the inside of the case mouths before first reloading and after every trimming, so that flat based bullets don't have to pop over the square inside of the mouth.
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I agree with the above. Boat tails help but a lot of hunting bullets are not and you should still be able to seat without a lot of effort.

You have a serious problem in that it should be very little effort to seat (new brass a bit more).

If you would list the press, types of dies (mfg) and the seater.

I have two seaters, RCBS comp and the Forster Comp. Both go about it different but line up a bullet better than the basic type.

PS: Look in your User CP area, I sent you a Personal Message as well (PM)
 
As per Guffey, I appreciate your correctness as I understand completely that what I have read from manuals, discussed with company reps, and gleaned off the net have left me with an incomplete understanding of my task. However, the issue I am having is frustrating and my attempt at diligent problem solving have so far proved fruitless. Honestly, I'm trying to improve my reloading technique, please address.
Here is what I'm working with: Caliber .243, Forster F/L sizing die, Nosler 95gr Ballistic tip, New unfired Winchester casing, Forster Micro Bullet Seater

Measurements with a Mitotoyo about a $170.00 model

Expander Ball .2415 95gr NBT .242 Sized case neck I.D .2415

O.D. Sized case neck rim .271 Case neck wall apx. .016

Finished product neck O.D. .271

I understand the need for quality cases, I usually load Norma cases and thought I would try these Winchesters to see if they made a difference and they didn't.
 
The Forster micrometer seat die uses a sliding sleeve under spring tension.

Does the sleeve slide up and down freely? You can compress it with your hand.
 
Your numbers do not look bad at all. That said as someone mentioned the neck inside diameter chamfer. Generally I just do mine using a hand tool or on the electric case prep center. A few twist of the hand is generally adequate. Next item of importance is seating straight and with flat base bullets, especially small flat base bullets, that can be difficult. Even with a slight mis-alignment it becomes easy to shave copper jacket material off the bullets. If you look closely while seating, even stopping half seated, note where the shaving is happening. If it is apparent only on one side then the bullets are not seating true to center line axis. This becomes real apparent if the finished rounds are checked with a concentricity gauge. The link just being one example of such a gauge. Again, to me your numbers do not look all that bad. Seating HPBT or any BT bullets generally goes easier. There are seating dies made to work around bullets not seating evenly, the RCBS COMPETITION FULL-LENGTH DIE SETS come to mind but there are plenty out there to choose from.

Flashole posted another great die as I was typing. The Forrester dies are very good.

Hopefully others have more and better suggestions.

Ron
 
Ron is pretty much on the stick with 'Competition' dies that use inserts.
Much better control on shoulder/neck sizing.

CONSISTANCY starts with the BRASS...
Guys used to sort by once fired, twice fired, thrice fired, etc.

Getting the shoulder/neck CONSISTANT BEFORE sizing/loading is why we anneal (soften) the neck to a CONSISTANT point before sizing.
Work hardening makes for brass that hates to resize properly.

'Shaving' is usually an issue with tapering the case mouth.
Proper inside taper *Should* allow the bullet to size the case neck.
Soft necks make seating the bullet MUCH easier.
 
One cheap neck sizer to consider is the Lee collet die. Gives a very consistent ID, and normally very concentric cases.
 
"...growing neck thickness..." Neck walls don't get thicker unless you're forming cases.
It's highly unlikely you'd get a lead cored bullet into a case mouth that is too small. Too small is where any "excessive neck tension" comes from. If it even exists.
"...always have the little shavings..." Says insufficient chamfering and deburring to me. Assuming said shavings are copper and not brass.
No$ler's 6mm calibre bullets aren't .242" diameter either. If your's are ,they're defective. Might be 'seconds'. Or you're reading the high priced "Mitotoyo". wrong. Which is a brand name, not a tool.
 
I appreciate your correctness as I understand completely that what I have read from manuals, discussed with company reps, and gleaned off the net have left me with an incomplete understanding of my task. However, the issue I am having is frustrating and my attempt at diligent problem solving have so far proved fruitless. Honestly, I'm trying to improve my reloading technique, please address.
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I will assume you have fired this rifle; had you ever gone to the range with a small group of very disciplined reloaders in this small part of Texas you would know the outside diameter of the case neck increases in daimeter when the case is fired and with little effort you could determine the inside diameter of the case neck. I fire the first round then remove the case and then stick the bullet in the next round into the neck of the fired case. There is nothing amusing or entertaining about finding there is no clearance between the bullet and fired case neck; because I insist the neck of the case must expand; nothing increases pressure like a case neck that is too tight for the chamber.

Point? I understand it is cool to mention Norma, Lepur and other expensive cases when reloading and comparing with cheaper cases. I do not do that. Again, when shooting the expensive cases you should have compared the outside diameter of the fired cases neck with the new, over the counter factor outside diameter of the necks.

And then there impressionable reloaders taking advise from a choir that recommends every new gadget like collet and bushing dies. There is a chance you have already gotten into that trap. From the big inning I have not added a lot if equipment that would elevate my status, my big concern is the fit between the outside of the case and inside of the chamber, I have insisted on having air between the chamber and case, I do not want a lot of air just a little and I insist the air be clean.

I have no ideal why reloaders insist the inside of the neck is tapered, if it was the bullet would increases in the amount of effort when seating. Again, there is nothing that works like the bullet being aligned with the neck of the case. I have two seating dies from RCBS, some reloaders insist the seating die comes with a bushing, my seating dies from RCBS come with guides. To make my money to further I purchased a die body and guides for different bullets.

Again, Herter sold die bodies with different guides, the guide set on the shoulder of the case; and then the bullet was dropped through the top of the guide, above that they had different bullet seater plugs. The nice thing about that arrangement the threads in the top of the die was the same for all of the dies, sizing and seating.

In later years that caused confusion because some reloaders screwed seating stems into the bull length sizers but it was possible to turn seating dies into universal primer punch dies. Or full length sizing dies into seating dies without guides.

F. Guffey
 
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