What causes bent 30-06 necks and how can they be fixed?

oneskilledshooter

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I have some 30-06 once fired Norma brass.

They were fired out of a buddy's browning BAR once and came from factory ammo.

Other cases that have been sized on the same press, same die and adjusted the same way are fine.

What could have caused the bent necks? The autoloader feeding? I don't want to use the cases as they are, but is there a way to fix them? Bulett tips are off center :(
 
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They may be annealed slightly softer and unevenly at the neck/shoulder area than the other brass. Possibly being pulled off center when the expander button is drawn out. Alternately and still assuming uneven annealing one side of the neck/shoulder may be collapsing slightly when seating the bullet. Make sure you lube the inner neck when sizing and a good inner neck chamfer may help for both sizing and seating. There is a tool/jig available for straightening loaded rounds to remove run out of the bullet and neck.
 
They may be annealed slightly softer and unevenly at the neck/shoulder area than the other brass. Possibly being pulled off center when the expander button is drawn out. Alternately and still assuming uneven annealing one side of the neck/shoulder may be collapsing slightly when seating the bullet. Make sure you lube the inner neck when sizing and a good inner neck chamfer may help for both sizing and seating. There is a tool/jig available for straightening loaded rounds to remove run out of the bullet and neck.

Thank you, that's interesting. I did trim them all to length, then chamfer/deburr with a lyman tool. Also lubed the inside of the neck. The necks were bent before seating, as I have some that have been sized, but not yet loaded.

Do you think the tool/jig is worth having around? I haven't heard of something like that. I am not too fussed about these Norma cases as I only have 20 of them, but I am trying to learn more about the causes and solutions to this for future reference.

What else could cause the bent necks? Defective sizing die? Seems unlikely to me..... Everything seems normal. I was not aware that the brass manufacturers anneal? That's interesting.
 
If they don't straighten out when you resize them, you have other issues.

The annealing won't make any difference at all.

I've cleaned up and used lots of range pick up brass. Some of it was dented and bent so badly I never thought it would be reloadable.

The odd time, some of it isn't.

I usually remove the decapping rod before full length resizing such brass. Then, lube the cases well, after cleaning and pass them through the full length resizing die. This isn't a procedure to done on a progressive press but on a single stage press.

If your single stage press is good and square, some of the newer ones aren't, and if your dies are concentric and square to the press, those cases will come out straight.

One other issue, if your inside sizing ball is slightly small and you're using flat base bullets, the bullet may not be seating in the case mouth squarely and entering at an angle.

Also, if your case mouths are not square as well, that will cause the bullets to be seated off center.

Hardened brass, can be an issue but not after only one firing.
 
What could have caused the bent necks? :(

Do you "see" bent necks or are you measuring neck runout with a with a gauge?

1. Firing commercial cases in long fat military chambers can cause the case to warp if the case is thinner on one side. (banana shaped case)

2. The most common reason of neck run out is caused by the decapper/expander button being locked down off center.

If your other reloaded ammunition is OK and has no runout then the Norma cases warped on firing and resizing made it even worse.

 
If they don't straighten out when you resize them, you have other issues.

I usually remove the decapping rod before full length resizing such brass. Then, lube the cases well, after cleaning and pass them through the full length resizing die. This isn't a procedure to done on a progressive press but on a single stage press.

If your single stage press is good and square, some of the newer ones aren't, and if your dies are concentric and square to the press, those cases will come out straight.

One other issue, if your inside sizing ball is slightly small and you're using flat base bullets, the bullet may not be seating in the case mouth squarely and entering at an angle.

Also, if your case mouths are not square as well, that will cause the bullets to be seated off center.

Hardened brass, can be an issue but not after only one firing.

I should mention that I have a lot of experience loading pistol on a progressive, but this is my first try for rifle. Press is an RCBS (rockchucker? the big one) that I got used. Single stage, of course. I don't know how old it is, but I think it is at least 20 years old. Dies are Lee (new). So I guess it sounds like maybe I should try and borrow another die to try out on the press first to make sure the press isn't out? Seems unlikely that the press could be out...... but anything is possible and something is certainly causing the issue.

I will have to check all of my other cases that I sized very carefully to make sure that they don't have any of the same issue. By checking I mean rolling on a flat surface - I usually use glass as it is probably the flattest thing I have on hand. I think that I trimmed these cases slightly (for uniformity) so it may be that they are not quite square, although that seems unlikely. I used a lyman trimmer. Perhaps the sizing die set too low on a case that is not trimmed square could cause this? I did set the sizing die very carefully as per instructions and it did not hit the rim....

I don't think it can be due to a case that is too small as I can see the problem when I roll the cases along a flat surface before I seat a bullet.

So whatever is going on, it sounds like when I correct the problem I will be able to fix these cases? or are these particular ones just pooched now?

Do you "see" bent necks or are you measuring neck runout with a with a gauge?

1. Firing commercial cases in long fat military chambers can cause the case to warp if the case is thinner on one side. (banana shaped case)

2. The most common reason of neck run out is caused by the decapper/expander button being locked down off center.

If your other reloaded ammunition is OK and has no runout then the Norma cases warped on firing and resizing made it even worse.


How could you lock it down off center? Would that be caused by a bent pin? I guess I check for off center with a mic?

Thanks for the help guys! I will check back later when I can get back to the bench.
 
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oneskilledshooter

It is very easy to have misalignment of the expander button and pull your necks off center. The lock nut on the expander button should not be tightened down until a case is in the shell holder and the ram is on the down stroke and has just entered the neck of the case. Using this method centers the expander button inside the case neck and greatly reduces runout.

"Normally" this will center the expander button inside the die and all you need to do is tighten the lock nut.

"BUT" if there are any dents, dings or extractor damage inside the extractor groove of the case, on the down stroke of the ram the shell holder is holding the case "inside" of the extractor groove and any damage there will cause the case to tilt on the down stroke and pull the necks off center.

The majority of gas operated rifles are over gassed to ensure they will function with a under powered ammunition. The problem with this is the bolt can be moving to the rear while the case is still gripping the chamber walls. The healthy tug by the extractor can damage the extractor groove and cause runout problems during reloading.
 
"...If they don't..." Yep. It's caused by the case whacking the rifle on the way out during ejection. Happens a lot with semi-autos. The sizer die should fix it. No special tools or jig or anything is required.
"...Hornday Ammunition Concentricity Tool..." B]Hornady's[/B] marketing.
 
Fire the crooked cases in your rifle and then check for concentricity, the BAR is hard on cases and may well have bent the case upon extraction. Firing the loaded round in a new and square chamber will straighten everything out. Sometimes a die can't fix all flaws especially if the previous chamber was near minimum and your die is generous. You just don't get enough contact or force to reform some flaws but firing it in your rifle will iron out those issues and then go from there. I don't even bother to check or trim any cases until they have been fired from my intended rifle, there are just too many variables until they have been formed to the chamber that I wish to shoot them from.
 
Fire the crooked cases in your rifle and then check for concentricity, the BAR is hard on cases and may well have bent the case upon extraction. Firing the loaded round in a new and square chamber will straighten everything out. Sometimes a die can't fix all flaws especially if the previous chamber was near minimum and your die is generous. You just don't get enough contact or force to reform some flaws but firing it in your rifle will iron out those issues and then go from there. I don't even bother to check or trim any cases until they have been fired from my intended rifle, there are just too many variables until they have been formed to the chamber that I wish to shoot them from.

Looks like you nailed it!

I just checked all the WIN cases and there are 12 that have the crooked necks. This is the exact number that I picked up from the range! I am relieved that the ones that were fired from my rifle are good. I have just enough WIN brass that is good to do my load development. It would have been nice to start with good new brass, but I can't find any that I would like to use. Nothing but Remington around.

Thanks so much for all your help guys! I have learned so much from everyone on here while I have taught myself to load from books and the internet (mostly books, I don't trust a lot of what is out there online). Sometimes I get stuck with a problem, but you guys always help me figure it out!
 
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