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Why do my cases stretch when I resize?

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02 January 2002, 03:13
LazoG
Why do my cases stretch when I resize?
Does anyone know what would be causing the cases to stretch during resizing? The inside of the die has been cleaned thoroughly, I've used a good amount of lube on the cases and on the insides of the neck I've also used mica with no effect. This problem has reoccured with different calibres (.243 & .223). I'm using Winchester brass and a full size die to do the resizing with. What am I doing wrong?
02 January 2002, 03:47
<heavy varmint>
You are most likely doing nothing wrong, your case necks are squeezed down at the top of the press stroke then drug back through the expander on the way out of the die, this will result in slight streching of the case, more so in many calibers than actually fireing them. Winchester brass is a little soft compared to others so that would also contribute to the cases stretching more but just trim them back down to size and load em up.
02 January 2002, 04:28
DannoBoone
Is this a new problem? Has it happened with
other brass? Is there any buildup on your
expanders?

I have heard that some expanders are not
polished as well as needed to prevent a
problem such as yours. If all else fails,
you can disassemble it down to the expander
ball & stem. Place the stem in a drill and
polish with 0000 steel wool and Flitz.

02 January 2002, 06:21
<David>
Are you using case lube in the necks? If not that may be the problem. I use Imperial sizing wax. It works great and is much easier to clean up than the other case resizing lubes.

------------------
David Sipe

Politicians and diapers have one thing.in common:
They should both be changed regularly, and for the same reason

02 January 2002, 08:48
<Big Stick>
Try the Redding bushing dies. Once you use them,you'll throw everything else away.........


(throw,not through)

[This message has been edited by Big Stick (edited 01-02-2002).]

02 January 2002, 13:52
Ray, Alaska
Lube the inside portion of the case's neck and see what happens. If you feel too much resistance when the expander is coming out of the case, it could be that it lacks lubricant. Some resistance is normal, but not too much of it.


02 January 2002, 15:09
LazoG
This problem is reoccuring and I have always had it, I haven't been reloading for very long though. I've been using RCBS Case Lube on the cases and on the inside of the necks and the cases still stretch a little. By the way what is an expander and what is the correct method of setting up the die(just checking)?
02 January 2002, 15:19
Carnivore
Try a collet neck sizer from Lee. I had excellent results in 22-250, 243, and 30-06. Less runout than several of my other die sets. I initally tried them because I hate lubing those little necks. I know people dog cuss Lee products but this one is a winner. No lube needed and they won't move the shoulder around.
02 January 2002, 16:05
<Oldmodel70>
Hornady makes carbide expander buttons in some calibers.......I have some, and they seem to work well, without streching cases.
02 January 2002, 18:44
243winxb
Lazog, An expander is part of the full length sizing die. It holds the decaping pin. The full length die sizes down the case mouth. The expander then opens the inside neck diameter to the correct size to hold the bullet. The case streching maybe this. Make sure your full length die is adjusted correctly. With the ram and shell holder in the full up posision screw down the die till it is tight onto the shell holder. Then back off the shell holder and turn the die down about 1/16 of a turn and lock in position. Now when u raise the shell holder u should feel it cam over. This is the correct setting. Hope this helps 243winxb
03 January 2002, 03:08
<heavy varmint>
LazoG, By your comments that it happens on severel different calibers and you are using lube on the inside of the neck I still think that your cases stretching is probably just the normal strethching associated with a full length sizeing die. Do you have dial calipers to measure the OAL of the case before and after sizeing? Can you give some numbers? You can polish the expander as has allready suggested, that will help some.
06 January 2002, 13:01
<Reloader66>
It is normal for any fired brass case to stretch when FL sized no matter how good or how poor the bass is. You must measure your brass and trim to your reloading manuals specs. The brass is worked most when FL sized. Using a neck size only die will reduce brass stretch but the cases must alway be fired in the same rifle. If you lube the inside of the case neck be sure you use powdered graphite or you may end up with a lot of cases that won't fire. Resizing wax is not used in side the case. You can polish the expander plug in your die with 0000 steel wool to make them work smoother when the case is sized to proper diameter. Get in the habit of using a nylon brush to clean the inside of the case neck before you size your cses.
06 January 2002, 13:18
<Slamfire>
I think you can get an elliptical expander ball from Redding, it is shaped like a football and is a bit easier on the cases when expanding. The collet dies should totally eliminate the probelm.
06 January 2002, 18:06
SDS
If this bothers you, try using the RCBS X-die, which is supposed to eliminate the need for trimming. I cannot personally recommend the product because I have no experience with it. I have used the Lee collet dies and I like them a lot.


07 January 2002, 01:11
Big Bore
Another trick that really reduced the number of times I have to trim due to stretch, is get rid of the expanding button that expands the case neck as you take the case OUT OF THE DIE. Deprime with a universal deprime die, size, and then neck expand with a Lyman M die or RCBS equivalent that expands the neck as the case GOES INTO THE DIE. I've proved it time and time again, two cases, fired, that measure the same length, size one with the decap/neck expander button in place, and one without the expander button and then expand with the M die, and the two cases almost always show that the one expanded with the decap rod/expander will be .001-.003" longer than the one expanded with the M die. Try it, what have you got to loose besides $10 or so.