Do dies really wear out?

Craig0ry

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So been reloading for 6 years now, and only recently been having troubles with one of my calibres, 308. So I got the dies(old) from a friend they were used, to what extent I don't know, and I only reload NATO spec brass that I got a whole pile from, I had to resize the brass a few times in order for it to chamber in my gun, trimmed of course too. Started on a new batch stuff I haven't previously loaded but the same headstamp and year and all came from the same pile. Resized each piece twice and then case trimmed, still won't chamber properly in the rifle, brass looks to be in excellent shape with no bulges. So my question is are my dies worn out to the point where they won't size properly or is something else going on Iam not aware of. They are rcbs SB dies I believe
 
Dies won't wear out but they can rust and be damaged by dirty brass.

Nato spec brass fired in miscellaneous rifles will require full length sizing with lots of lube and a press that does not spring... to me it is not worth the effort, I would simply sell it for scrap and buy quality brass.

I suspect your press may be springing a bit and you are not really full length sizing...
 
You may have done this and not mentioned it..... have you measured the brass??? you can then see if it is indeed the brass causing the problem, and also where it is out of spec....

Measure and repost......
 
Iam actually unfamiliar with the term springing when it comes to reloading, all the brass is twin city dated 1969, or lake city dated 1973 i believe,I thought this was fairly decent quality brass, and lapua brass is too expensive for my blood. Have a ton of Winchester brass fired in a worn out RCMP qualifying rifle. This is my first issue with this NATO brass.
 
You may have done this and not mentioned it..... have you measured the brass??? you can then see if it is indeed the brass causing the problem, and also where it is out of spec....

Measure and repost......

I'll do that when Iam home from work length I know is fine, but as for diameter which I suspect is where my issue is, I haven't measured
 
At the risk of asking questions one would ask of a newbie, the following come to mind:

1. Just to confirm. Have you successfully loaded military brass with those dies and that rifle?

2. What sort of press are you using? If it's a C press, then as guntech suggests, the press itself may be distorting or stretching just a bit

3. Did you do the standard set-up - raise the ram, screw down the sizing die until it touches, lower the ram and then screw the die down another half-turn before locking it in place?

4. What rifle and how old?

I've not heard of having to resize twice, but maybe I don't get out much. I too would be interested in seeing the results of your measuring.
 
At the risk of asking questions one would ask of a newbie, the following come to mind:

1. Just to confirm. Have you successfully loaded military brass with those dies and that rifle?

2. What sort of press are you using? If it's a C press, then as guntech suggests, the press itself may be distorting or stretching just a bit

3. Did you do the standard set-up - raise the ram, screw down the sizing die until it touches, lower the ram and then screw the die down another half-turn before locking it in place?

4. What rifle and how old?

I've not heard of having to resize twice, but maybe I don't get out much. I too would be interested in seeing the results of your measuring.

1. You bet, loaded successfully before
2. It's a bonanza single stage not a c type
3. Yes to that as well, the shell holder is almost touching when the boom is raised.
4. Rifle is a rem 700vtr and about 3 years old.
And I was told to resize twice as the military brass has a thicker case wall than commercial
 
1. You bet, loaded successfully before
2. It's a bonanza single stage not a c type
3. Yes to that as well, the shell holder is almost touching when the boom is raised.
4. Rifle is a rem 700vtr and about 3 years old.
And I was told to resize twice as the military brass has a thicker case wall than commercial

The sizing die has to bottom hard onto the shell holder to full length size.
 
The majority of military 7.62 ammunition is fired in machine guns, these machine guns have chambers at least .002 larger in diameter and much longer headspace settings than commercial SAAMI chambers.

When you fire a cartridge case the chamber pressure causes the brass cartridge case to stretch to the chamber dimensions. As the bullet exits the barrel the chamber pressure dorps to zero and the case tries to spring back to its original dimensions. The now smaller case exits the chamber and is slightly larger than before it was fired.

When the case is full length resized the brass is compressed to factory dimensions "inside the die" and when the case is removed from the die the brass can spring back larger (fatter and longer) than the internal dimensions of the resizing die (brass spring back or memory)

When I buy "ANY" once fired military 5.56 or 7.62 I resize it the first time with a small base die to bring the case back to "minimum" factory dimensions. This is because the are fired in longer and fatter chambers and the brass has a memory and wants to spring back to its original size.

This is why they make micrometers and vernier calipers and people can measure their fired cases and their resized cases and see what they are doing.

I have a bolt action .223 and two AR15 rifles and the headspacing setting are not the same with the AR15s having longer headspace settings. I have a Lee .223 die that if the die is set up to make hard contact with the shell holder and cam over it will make the cases .010 shorter than their fired length. This is over resizing these cases and why they make case gauges, below is the best gauge going. With just one Hornady cartridge case headspace gauge you can measure every caliber cartridge you have.

gauge002_zpsd2792ffa.jpg


You simply measure your fired length and bump the shoulder .001 to .002 for a bolt action and .003 to .004 for a semiauto. You do not follow the dies directions for this and you start high and work down to get the correct shoulder bump. At a minimum a full length resizing die that cams over will make your cases .002 shorter than the GO gauge or minimum headspace. This resized cartridge case headspace length will vary with each die and shell holder so die setup is critical for longer case life and preventing case head separations.

shouldersetback_zps59bf1b04.jpg
 
I didn't realize you were supposed to bottom it out, I guess I've been loading wrong for quite some time

You haven't been loading wrong necessarily, just not completely full length resizing. A lot of reloaders don't, until they have to, which is where it sounds like you are with this batch of brass. Once you get the die set up properly, you will feel the shoulder get "bumped" back as you pull the lever on your press ALL the way down. Then your brass will truely be FL sized like the third case in the pic in Eds post, (may also require a trim!) Right now your brass is getting more of a neck sizing like the brass in the middle in the same pic above.

Good luck, and post updates w/ your progress.
 
If you want to FL resize, you usually add a bit of preload, after the shellholder bottoms on the die.

Below on the right is a standard RCBS #10 shell holder, on the left is a Redding custom shell holder from a set of fiver shell holders. On top of the dark Redding shell holder you can see +.004, meaning this shell holder is .004 taller than a standard shell holder. I use the +.004 shell holder for full length resizing the cases for my AR15 rifle that have longer military headspace. I use the +.002 shell holder for sizing my bolt action .223 case because this rifle has shorter civilian headspace. The basic thumb rule for shoulder bump is .001 to .002 on bolt actions and .002 to .004 on semiautomatics like my AR15 rifles. If you set your dies up per the instructions you will over resize the cases and shorten your case life.

shellholders_zps0f9bb695.jpg


customSH_zpsae750915.jpg


Your head clearance is the "air space" between the rear of the case and the bolt face. When you over resize the case you push the shoulder back too far and create too much head clearance. This head clearance or "air space" is the distance the case stretches when fired. If the case stretches too far the brass will stretch and thin in the base web area and cause case head separations.

HEADCLEARANCE-a_zps53089f07.jpg


Below is an example, BUT the rifles actual headspace was not given on this new Savage .308 rifle and I believe it was set very close to the GO gauge. Meaning these cases were not greatly over resized with the dies adjusted to make hard contact and the press reaching cam over.

308fail-1_zps30d387ab.jpg


308fail2-1_zps3ca31f6b.jpg


It is also possible to under resize the case and make it "LONGER" than its fired length by having too much air gap between the shell holder and the die. When you full length resize you squeeze the brass inside the die and the brass can only move upward. This causes the shoulder of the case to move forward and the cartridge case headspace length increases. Meaning the case might not even fit in the chamber, so you can make your cases too long and you can make your caces too short. Your looking for the "middle" ground where your case fits the chamber with just a "little" wiggle room.
 
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This thread should be "stickied" so that other new reloaders can learn a thing or two. It never hurts to hear others experiences, problems, and the fix. Thanks for the above diagrams!!
 
I picked up a used Lee die set for 243 winchester and when I full length resized the brass was tighter when closing the chamber and this was from brass fired in that rifle. Got to checking and found the expander with the decapping pin was adjusted to low giving the false impression that the die was bottoming out to the shell holder. Readjusted the expander and all works as it was suppose to. Might be something to check.
 
Well I lowered the die until it hit the shell holder plus a little more while still being able to do a full stroke, And what do ya know! it solved my problem. Thanks guys!, and now onto a new topic, I picked up a .30 neck sizer, haven't used it yet, but once all this brass has gone through my rifle I should be able to start using just the neck sizer and a case trimmer correct?
 
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