Case mouth not being closed enough by die

H Wally

H Wally

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Here's how it happend. Cranked out 50 rds no problem. Had a jam on a piece of brass like you might get with insufficient lube. Worked the press open, cartridge seemed fine. However, after the die started producing loose mouthed brass and brass with loose necks but tight transitions to the shoulder.



Mmmk. My die is tightened and locked down slightly past the highest point the shell holder will go, ensuring that the case fully enters the die.
Some of the time the case will pass freely over the expander ball on the up stroke, fully enter the die with some resistance, then pass down over the expander ball without touching it at all. These case mouths will allow a bullet to fall into the case either with little resistance or none.


The other 2/3 of the time it seems to work ok, though it's the first time I've used the die and have not gone further than depriming the brass.



It's a Hornady Durachrome die in 6.5x55. Die has been inspected and is clean and in seemingly good order.

Brass in question is winchester and graf 6.5x55.

Expander ball is .263


Any ideas? Something's stopping the die from crushing the case mouth down to the degree that the expander ball can reopen it to the correct diameter. I've never come across this and can't figure it out.

Would using a Lee shell holder with a hornady die set make a difference? Concievably, could hornady have made thinner case holders while lee left less metal on the bottom of their dies?

EDIT - Some of the F/L resized brass that are faulty show strong rings where it transitions from the case neck to shoulder. The bullet will pass through the mouth but stop at the ring at the transition between the case neck and shoulder.
 
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Not entirely sure what you mean by over centering ( rcbs press that case travels upwards when handle goes down), so can't answer that directly - I put shellholder all the way up, screwed die all the way down against it, backed shellholder off and screwed the die in 1/4 further. I've gone so far as a complete turn in case there was something I was missing, but no difference.
 
I had that situation once with a bad lot of old IVI brass in .308, the problem was brass that was too thin at the neck. Not likely that it could happen with brass from two different manufacturers though. Try a different die or get a case neck micrometer and measure neck thickness.
 
They're roughly the same. I'm using a set of calipers but comes out at .011 to .015 or so. Some variation could be my fault or left over crimp, burrs etc.
 
My thought is that possibly you have gotten a "bad" die. Highly unlikely but it has happened in the past.

One way to check is to measure the width of the neck after you resize. Use a manual to find the correct measurement that you should have after resizing. If the width is correct then maybe the wall thickness of the brass is too thin.
 
The published neck width in three different manuals is .297 outside diameter.

ALL of my brass, good and bad, comes out at .290 outside diameter.
 
Is this a 3 die set? Some older sets of dies had one for resizing and a seperate die for expanding and depriming. Could be some mismatched combination.

Did you check the expander ball rod is still straight?

First thing that occurs to me is that when you jammed it the rod got a bit bent and with the expander ball sitting at a bit of an angle its over expanding the necks. They should be coming out out of round if thats the case.

Another idea that might be a bit far fetched is that the expander is cracked and now bigger than it was. Seems very unlikely but when you have ruled out the more obvious....
 
H Wally said:
- Some of the F/L resized brass that are faulty show strong rings where it transitions from the case neck to shoulder. .
Click to expand...


I think what you are describing is called a doughnut".


Total guess to throw out there.....I don't know what durachrome dies are but if they are chrome lined I would guess you lost some chrome in the neck.




The 2 Hornady dies I have are terrible for neck problems, my 7Rem mag necks down to much then it is hard to get the case over the expander ball. I thought it was bad untill I special ordered a set of 7x65R dies from Hornady. That set of dies necks the brass down so bad you cannot get them over the expander ball without smacking the press handle with a hammer. Case lube inside the neck is absolutely mandatory. Of course then the necks crack from being over worked so bad, not good for brass that cost $160 for 100.
 
vagrantviking said:
Is this a 3 die set? Some older sets of dies had one for resizing and a seperate die for expanding and depriming. Could be some mismatched combination.

Did you check the expander ball rod is still straight?

First thing that occurs to me is that when you jammed it the rod got a bit bent and with the expander ball sitting at a bit of an angle its over expanding the necks. They should be coming out out of round if thats the case.

Another idea that might be a bit far fetched is that the expander is cracked and now bigger than it was. Seems very unlikely but when you have ruled out the more obvious....
Click to expand...

The expander ball is not the issue I think. My main reason for this is that it you can feel when it touches the case mouth, and on the bad brass it doesn't touch them at all.

That leads me to conclude that the die itself is to blame, because if the expander ball was too big, cracked, or on an angle you would feel it contact the case as it passed over. It doesn't. I have also measured it and it is exactly 0.264, which is exactly what it should be. Instead the unsized case fits in normally, compresses, then comes out with the body but not the neck being sized, despite being completely inside the die as far as it will go. The brass is not overly short, as I've measured them all.

Crankbender said:
I think what you are describing is called a doughnut".


Total guess to throw out there.....I don't know what durachrome dies are but if they are chrome lined I would guess you lost some chrome in the neck.




The 2 Hornady dies I have are terrible for neck problems, my 7Rem mag necks down to much then it is hard to get the case over the expander ball. I thought it was bad untill I special ordered a set of 7x65R dies from Hornady. That set of dies necks the brass down so bad you cannot get them over the expander ball without smacking the press handle with a hammer. Case lube inside the neck is absolutely mandatory. Of course then the necks crack from being over worked so bad, not good for brass that cost $160 for 100.
Click to expand...

Geez. Maybe I should just cut my losses and get a lee die eh? I've looked inside the die with a magnification glass and strong light and it seems fine - no imperfections, bumps, or flaws whatsoever. Not even a ripple in the finish.
 
What about the bullets ? I had some .264 Remington Core locks (dual diameter) that would not seat in a case after being neck sized with Hornady 6.5 neck die, I narrowed it down to a bullet issue since I could seat Nosler partition with the usual resistance and neck stiffness..

If it is a die issue I would call Hornady, my only experience calling them was very good. Like RCBS they ship you part you need, no questions asked, no charge.


food for thought.
 
Pathfinder said:
What about the bullets ? I had some .264 Remington Core locks (dual diameter) that would not seat in a case after being neck sized with Hornady 6.5 neck die, I narrowed it down to a bullet issue since I could seat Nosler partition with the usual resistance and neck stiffness..

If it is a die issue I would call Hornady, my only experience calling them was very good. Like RCBS they ship you part you need, no questions asked, no charge.


food for thought.
Click to expand...


Bullets tried are 0.263-0.265, all slide right through, even when brass has been full length sized without the expander ball. Bullets are Speer and Nosler, 140gr fmj, 140gr sp, 140gr nosler ballistic tip and 160gr sp.

I'll give hornady a call and see what they say. Thanks for the info and suggestions guys!
 
Crankbender said:
I think what you are describing is called a doughnut".


Total guess to throw out there.....I don't know what durachrome dies are but if they are chrome lined I would guess you lost some chrome in the neck.




The 2 Hornady dies I have are terrible for neck problems, my 7Rem mag necks down to much then it is hard to get the case over the expander ball. I thought it was bad untill I special ordered a set of 7x65R dies from Hornady. That set of dies necks the brass down so bad you cannot get them over the expander ball without smacking the press handle with a hammer. Case lube inside the neck is absolutely mandatory. Of course then the necks crack from being over worked so bad, not good for brass that cost $160 for 100.
Click to expand...

Shouldn't get much of a doughnut unless you're turning necks I think. Try taking the expander plug out of the die and polish it with buffing compound on a muslin wheel. That may help stop the expander from sticking on the down stroke, did with most of my dies of different makes. The one Hornady set I used had a tear drop shape expander and was very smooth operating. As for H Wally, sounds like gremlins! Were the first cases you resized giving enough neck tension to hold a bullet?
 
Finger Toes said:
Shouldn't get much of a doughnut unless you're turning necks I think. Try taking the expander plug out of the die and polish it with buffing compound on a muslin wheel. That may help stop the expander from sticking on the down stroke, did with most of my dies of different makes. The one Hornady set I used had a tear drop shape expander and was very smooth operating. As for H Wally, sounds like gremlins! Were the first cases you resized giving enough neck tension to hold a bullet?
Click to expand...


Turning necks?

The first cases were good. Can't figure it out. Ran about 50 through, all fine and good. One got stuck, everything went to hell in a hand basket.
 
H Wally said:
Turning necks?

The first cases were good. Can't figure it out. Ran about 50 through, all fine and good. One got stuck, everything went to hell in a hand basket.
Click to expand...

Sorry, turning necks was intended for crankbenders thoughts about doughnuts. That is really weird with the neck tension. Could there have been an insert in the neck sizing part of the die that got knocked out? Seems highly unlikely but......
 
Worth asking. The degree that it's out I'm almost wondering if the chroming didn't just slip out and disappear without my noticing. If it happend as one piece, uniformly where the neck joins the shoulder in the die it wouldn't be visible (because the transition would hide it) and could possibly be thick enough to cause it. No silverly or otherwise metalic bits anywhere though.

Still no reply from hornady either. Might give them a call, didn't notice if they had a toll free number or not.
 
Heres a long shot - is the expander ball sitting too high in the die? On Lee dies this can be a problem and it typically happens after a jam. The expander is held by a collet which slips when distressed.
 
Case wall variation of .011 to .015 is large. I've often experienced thin neck brass on european brass(prvi partizan, igman and graf). Bullets won't be held tight in neck, and many loading companies refuse to admit problem. I received a replacement hornady sizing die in .357 mag exactly the same as first one(bullets loose in neck(not an expander problem)). Problem sometimes reduced by using nickel-plated brass(thicker necks). good luck
 
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