.223 / 5.56 brass cracked neck

tangolima · January 21, 2023, 11:50 AM

I load for my AR-15 A2 with LC brass. I have noticed the neck cracks earlier than any other calibers I have been loading. Annealing every 5 loads, they still can't last more than 10 loads.

Perhaps the small caliber stretches the neck brass more than bigger calibers percentage-wise? Turning the neck thinner may help? It is not a big deal as brass are plentiful to pick up. Just curious.

Perhaps it is the brass composition of LC brass. It is for military use. They only care the first load.

-TL

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**44 AMP** · January 21, 2023, 01:10 PM

Likely its the brass. LC from what years????

possibly your annealing process isn't annealing enough???

Still, 10 loads from rife brass is not "short life".

Possibly its your AR rife. Even the best autoloaders are not as gentle on the brass as manual actions.

Also possible to be a combination of factors.

If you had the equipment, I would run that ammo through a bolt action and your AR and see if there were any differences at all in case life. Do everything exactly the same, just shoot them from a different rifle for comparison. If it's only the brass, I would expect case failure to be approximately same rate in both rifles.

tangolima · January 21, 2023, 01:35 PM

LC from different years. One thing I also noticed is that the case volume varies a lot even within the same years. Some said the brass were sourced from different suppliers. So I just sort them by weight.

I don't have a bolt gun in that caliber. However I follow the same procedure for any other calibers, bolt and auto. They routinely shoot 20 or more loads. But they are commercial brass 6.5mm or bigger.

Maybe I should let go of LC after I run out this batch. They are not that great anyway.

-TL

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Marco Califo · January 21, 2023, 02:53 PM

I keep my LC 5.56 brass sorted by sourcing block. For example, I have 1000 '98-ish, work great. I can identify ~500 desert feral pickup '07-09 that I am retiring after putting through 2 more loadings after scrounging them. They are surplus now that I have plenty of better brass.
I have never sorted by weight; if years are mixed I am skeptical sorting by weight does anything for you. I have never had any case neck issues.
If you can find new Starline 5.56, or never loaded LC, you could compare them to yours and maybe prove or disprove whether this is a brass issue or not.
My LC once fired came from Bartlett Reloaders, bought from USGI ranges, cleaned a Primer pockets processed. I have confidence they are what they claim to be.
Mixed range pickup (like the giant crate at my range) in my opinion, adds too many variables to enable root cause sleuthing.
I think the brass does not sound like your culprit, something else is probably going sideways.

**Unclenick** · January 21, 2023, 05:03 PM

Tangolima,

What is the neck OD you measure over the bullet before firing, and what is it after firing? If your chamber's neck is wider than normal, you could be getting extra stress in that area.

Another possibility is you are overheating the brass when you anneal it. If it gets too hot, grain growth starts to occur, and that lowers the tensile strength of the brass.

tangolima · January 21, 2023, 06:34 PM

Unclenick. I have 0.247" before firing, and 0.252" after. The chamber neck may be a bit on the generous side. It is a NATO 5.56 chamber. That may be why. Good point. I will look for brass with thicker neck wall. Will give up LC anyway.

There has been debates on weight sorting. I think it makes sense. The outside dimensions are fixed (same die meeting saami). Very similar brass density. The weight must give direct indication of internal volume.

-TL

PS. I have RWS brass with 0.249" before firing. It may work better.

Wait. I have 0.242" before seating bullet. The die neck is too tight and it is over working the brass neck. Oh boy. Another bushing die? Nah, I just increase the annealing frequency to every 2 loads.

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**44 AMP** · January 21, 2023, 06:49 PM

Quote:

The weight must give direct indication of internal volume.

Generally yes, however sometimes differences in brass alloy will make a measurable difference.

Internal volumes from GI brass with the same arsenal headstamps can vary from year to year, different production runs, slightly different alloys, powders, etc. The military has them loaded to a given range of pressure and velocity specs and the arsenals will adjust powder volumes to meet that, and each production batch might not be consistent in case volume or powder charge from the year before.

As handloaders we need greater consistency lot to lot, as we simply do not have the same resources available as ammo makers.

Rimfire5 · January 21, 2023, 06:57 PM

tangolima,

You didn't indicate whether your loads were on the hot side or mid-range on the load table you're using.
I find that brass stress and neck splits occur much more frequently with loads close to P-max.

I generally shoot Lapua brass in my bolt actions and get about 20 reloads or more from my brass. The primer pockets generally wear out before case necks split but I do find a split neck every once in a while.

In my ARs, ejections do too much damage to the brass to get the benefits of shooting Lapua and trying to get lots of reloads, so I too use brass that is cheaper.

That said, I rarely see case neck splits with 6 to 8 reloads of cheaper brass, unless I am pushing P-max.
Even loading close to P-max, I see more primer flattening, primer loosening and headstamp erasing than I see neck splits.

tangolima · January 21, 2023, 07:24 PM

Brass neck wall thickness varies. I have seen as thin as 0.010" and as thick as 0.013". Sizing die must cover the min. Die neck diameter

0.224 + 0.02 - 0.002 = 0.242"

The chamber neck diameter must cover the max

0.224 + 0.026 + 0.002 = 0.250"

The difference is 3.3% for .22 cal, and 2.4% for .30 cal. Smaller bullet diameter does work the brass harder, I'm afraid.

-TL

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tangolima · January 21, 2023, 07:28 PM

Rimfire. My load is mid range.

Ejection dents up brass. But I also have auto loaders for other calibers.

-TL

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Scorch · January 21, 2023, 08:25 PM

Quote:

Perhaps it is the brass composition of LC brass.

Could be the brass, could be the firearm.

Metal god · January 22, 2023, 01:54 AM

What dies are you using ? I also agree 10 reloads is not to bad with an auto loader .

I ask about dies because most standard dies size down the neck way to much that then requires the expander to pull back through and resize the neck to the proper diameter . I use Bushing dies with the expander installed but it does not need much force to pull it back through . I use the expander because I don't turn my necks so I use the expander the align the inside of the necks with the case body .

Annealing every 4 or 5 times "should" be good enough . Are you keeping really close track of the cases ? Meaning are any of the cases being reloading more then 4 or 5 times before annealing ? Are most of the case necks cracking or only a few of many ?

tangolima · January 22, 2023, 02:16 AM

I'm using Hornady full-length. It indeed sizes the neck too much to cover the thinnest brass neck thickness. I thought of getting a bushing die, but I'm too cheap to spend the $80. 5.56mm brass practically free, and it doesn't cost much to anneal often. I keep good record of the # of loads.

10 loads is not bad. Not really worrying about that. Mostly curiosity.

-TL

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Ifishsum · January 22, 2023, 03:44 AM

My AR patterns tend to put a little gouge in the neck from the edges of the barrel lugs...and my brass tends to get a hole near the neck/shoulder junction that doesn't necessarily extend all the way to the mouth, and I've always felt those nicks were the main cause or at least a contributing factor. I have lots of .223 brass so I do not bother to anneal, and I tend to start seeing this failure after 6-9 loadings depending on the brand of brass. FWIW, LC seems to last at least a couple loads longer for me than most of the commercial stuff.

jetinteriorguy · January 22, 2023, 09:21 AM

Try sizing with a Redding body only die followed by a Lee Collet Neck die. This combo is very easy on brass. Not only better on brass but the added benefit of little to no runout.

tangolima · January 22, 2023, 11:20 AM

Quote:

Originally Posted by Ifishsum

My AR patterns tend to put a little gouge in the neck from the edges of the barrel lugs...and my brass tends to get a hole near the neck/shoulder junction that doesn't necessarily extend all the way to the mouth, and I've always felt those nicks were the main cause or at least a contributing factor. I have lots of .223 brass so I do not bother to anneal, and I tend to start seeing this failure after 6-9 loadings depending on the brand of brass. FWIW, LC seems to last at least a couple loads longer for me than most of the commercial stuff.

Aha. Mine also has the exact same feature. That may well be the real cause. I noticed it on occasion but didn't make the connection. I suppose I can do something to increase the bolt speed to avoid that.

Thanks for the info.

-TL

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**44 AMP** · January 22, 2023, 01:22 PM

Quote:

I suppose I can do something to increase the bolt speed to avoid that.

Just out of curiosity, if your brass is getting nicked/damaged from striking a sharp edge on the way into the chamber, how is striking that edge faster going to help??

There are situations where "slamming it in there harder" produced the desired results. Don't see where faster bolt speed will reduce damage to brass, if anything I would think slower would be "gentler".

tangolima · January 22, 2023, 01:51 PM

It is during extraction/ejection rather. The ejector keeps a strong bias on the brass head. As soon as the mouth clears the chamber, it starts to tilt towards the ejection port, dragging itself on the teeth of lugs. If the bolt goes fast, it won't has time to tilt enough.

-TL

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Metal god · January 22, 2023, 03:27 PM

I had some feed ramps doing that . I took some small files to the edges . I assume I don’t need to say don’t get to happy with the files ;-)

tangolima · January 22, 2023, 03:38 PM

I may do the same after identifying the guilty teeth. I guess I just to smooth them a bit. Not going to touch the bearing surface for the lockup.

-TL

Sent from my SM-N960U using Tapatalk

**44 AMP** · January 22, 2023, 06:21 PM

Quote:

If the bolt goes fast, it won't has time to tilt enough.

Ok, I can see that. I would point out that there is a fine line between getting the bolt carrier assy to move backwards faster AFTER it unlocks, and still keeping the unlocking at the proper point.

Unlocking too soon, because the carrier is being pushed back harder, in order to move it faster, in order to (hopefully) reduce or eliminate "dinging" the extracting case, would not be a good idea, I think.

Slight stoning or filing to break the sharp edge might do it, but then again, it might not. You'd have to try it and see, I think.

tangolima · January 22, 2023, 06:41 PM

I was thinking about increasing the gasing a little. Loading the load hotter, using a slower powder etc.

I am not really desperate to resolve the issue. Mostly it is driven by curiosity.

BTW, I have put about 1k rounds through this rifle. Cleaned it only twice. It is a cheap A2. Once a while I can shoot better than 1moa 10-round groups with its peep sight. But l found it less and less frequent. For the heck of it, I put a sub-$100 lpvo scope on it. Now that sort of groups becomes routine. It is my failing eyesight. No fun getting old. More funds on optics.

-TL

Sent from my SM-N960U using Tapatalk

January 21, 2023, 11:50 AM	#1
tangolima Senior Member Join Date: September 28, 2013 Posts: 3,816	.223 / 5.56 brass cracked neck I load for my AR-15 A2 with LC brass. I have noticed the neck cracks earlier than any other calibers I have been loading. Annealing every 5 loads, they still can't last more than 10 loads. Perhaps the small caliber stretches the neck brass more than bigger calibers percentage-wise? Turning the neck thinner may help? It is not a big deal as brass are plentiful to pick up. Just curious. Perhaps it is the brass composition of LC brass. It is for military use. They only care the first load. -TL Sent from my SM-N960U using Tapatalk

January 21, 2023, 01:10 PM	#2
44 AMP Staff Join Date: March 11, 2006 Location: Upper US Posts: 28,820	Likely its the brass. LC from what years???? possibly your annealing process isn't annealing enough??? Still, 10 loads from rife brass is not "short life". Possibly its your AR rife. Even the best autoloaders are not as gentle on the brass as manual actions. Also possible to be a combination of factors. If you had the equipment, I would run that ammo through a bolt action and your AR and see if there were any differences at all in case life. Do everything exactly the same, just shoot them from a different rifle for comparison. If it's only the brass, I would expect case failure to be approximately same rate in both rifles. __________________ All else being equal (and it almost never is) bigger bullets tend to work better.

January 21, 2023, 02:53 PM	#4
Marco Califo Senior Member Join Date: April 4, 2011 Location: LA (Greater Los Angeles Area) Posts: 2,598	I keep my LC 5.56 brass sorted by sourcing block. For example, I have 1000 '98-ish, work great. I can identify ~500 desert feral pickup '07-09 that I am retiring after putting through 2 more loadings after scrounging them. They are surplus now that I have plenty of better brass. I have never sorted by weight; if years are mixed I am skeptical sorting by weight does anything for you. I have never had any case neck issues. If you can find new Starline 5.56, or never loaded LC, you could compare them to yours and maybe prove or disprove whether this is a brass issue or not. My LC once fired came from Bartlett Reloaders, bought from USGI ranges, cleaned a Primer pockets processed. I have confidence they are what they claim to be. Mixed range pickup (like the giant crate at my range) in my opinion, adds too many variables to enable root cause sleuthing. I think the brass does not sound like your culprit, something else is probably going sideways. __________________ ............

January 21, 2023, 05:03 PM	#5
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,061	Tangolima, What is the neck OD you measure over the bullet before firing, and what is it after firing? If your chamber's neck is wider than normal, you could be getting extra stress in that area. Another possibility is you are overheating the brass when you anneal it. If it gets too hot, grain growth starts to occur, and that lowers the tensile strength of the brass. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

January 21, 2023, 06:34 PM	#6
tangolima Senior Member Join Date: September 28, 2013 Posts: 3,816	Unclenick. I have 0.247" before firing, and 0.252" after. The chamber neck may be a bit on the generous side. It is a NATO 5.56 chamber. That may be why. Good point. I will look for brass with thicker neck wall. Will give up LC anyway. There has been debates on weight sorting. I think it makes sense. The outside dimensions are fixed (same die meeting saami). Very similar brass density. The weight must give direct indication of internal volume. -TL PS. I have RWS brass with 0.249" before firing. It may work better. Wait. I have 0.242" before seating bullet. The die neck is too tight and it is over working the brass neck. Oh boy. Another bushing die? Nah, I just increase the annealing frequency to every 2 loads. Sent from my SM-N960U using Tapatalk Last edited by tangolima; January 21, 2023 at 06:48 PM.

January 21, 2023, 01:35 PM	#3
tangolima Senior Member Join Date: September 28, 2013 Posts: 3,816	LC from different years. One thing I also noticed is that the case volume varies a lot even within the same years. Some said the brass were sourced from different suppliers. So I just sort them by weight. I don't have a bolt gun in that caliber. However I follow the same procedure for any other calibers, bolt and auto. They routinely shoot 20 or more loads. But they are commercial brass 6.5mm or bigger. Maybe I should let go of LC after I run out this batch. They are not that great anyway. -TL Sent from my SM-N960U using Tapatalk

January 21, 2023, 06:57 PM	#8
Rimfire5 Senior Member Join Date: January 2, 2009 Location: Northern Virginia Posts: 922	tangolima, You didn't indicate whether your loads were on the hot side or mid-range on the load table you're using. I find that brass stress and neck splits occur much more frequently with loads close to P-max. I generally shoot Lapua brass in my bolt actions and get about 20 reloads or more from my brass. The primer pockets generally wear out before case necks split but I do find a split neck every once in a while. In my ARs, ejections do too much damage to the brass to get the benefits of shooting Lapua and trying to get lots of reloads, so I too use brass that is cheaper. That said, I rarely see case neck splits with 6 to 8 reloads of cheaper brass, unless I am pushing P-max. Even loading close to P-max, I see more primer flattening, primer loosening and headstamp erasing than I see neck splits.

January 21, 2023, 07:24 PM	#9
tangolima Senior Member Join Date: September 28, 2013 Posts: 3,816	Brass neck wall thickness varies. I have seen as thin as 0.010" and as thick as 0.013". Sizing die must cover the min. Die neck diameter 0.224 + 0.02 - 0.002 = 0.242" The chamber neck diameter must cover the max 0.224 + 0.026 + 0.002 = 0.250" The difference is 3.3% for .22 cal, and 2.4% for .30 cal. Smaller bullet diameter does work the brass harder, I'm afraid. -TL Sent from my SM-N960U using Tapatalk

January 21, 2023, 07:28 PM	#10
tangolima Senior Member Join Date: September 28, 2013 Posts: 3,816	Rimfire. My load is mid range. Ejection dents up brass. But I also have auto loaders for other calibers. -TL Sent from my SM-N960U using Tapatalk

January 22, 2023, 01:54 AM	#12
Metal god Senior Member Join Date: April 10, 2012 Location: San Diego CA Posts: 6,875	What dies are you using ? I also agree 10 reloads is not to bad with an auto loader . I ask about dies because most standard dies size down the neck way to much that then requires the expander to pull back through and resize the neck to the proper diameter . I use Bushing dies with the expander installed but it does not need much force to pull it back through . I use the expander because I don't turn my necks so I use the expander the align the inside of the necks with the case body . Annealing every 4 or 5 times "should" be good enough . Are you keeping really close track of the cases ? Meaning are any of the cases being reloading more then 4 or 5 times before annealing ? Are most of the case necks cracking or only a few of many ? __________________ If Jesus had a gun , he'd probably still be alive ! I almost always write my posts regardless of content in a jovial manor and intent . If that's not how you took it , please try again .

January 22, 2023, 02:16 AM	#13
tangolima Senior Member Join Date: September 28, 2013 Posts: 3,816	I'm using Hornady full-length. It indeed sizes the neck too much to cover the thinnest brass neck thickness. I thought of getting a bushing die, but I'm too cheap to spend the $80. 5.56mm brass practically free, and it doesn't cost much to anneal often. I keep good record of the # of loads. 10 loads is not bad. Not really worrying about that. Mostly curiosity. -TL Sent from my SM-N960U using Tapatalk

January 22, 2023, 03:44 AM	#14
Ifishsum Senior Member Join Date: September 15, 2005 Location: Oregon Posts: 1,033	My AR patterns tend to put a little gouge in the neck from the edges of the barrel lugs...and my brass tends to get a hole near the neck/shoulder junction that doesn't necessarily extend all the way to the mouth, and I've always felt those nicks were the main cause or at least a contributing factor. I have lots of .223 brass so I do not bother to anneal, and I tend to start seeing this failure after 6-9 loadings depending on the brand of brass. FWIW, LC seems to last at least a couple loads longer for me than most of the commercial stuff.

January 22, 2023, 09:21 AM	#15
jetinteriorguy Senior Member Join Date: April 28, 2013 Posts: 3,173	Try sizing with a Redding body only die followed by a Lee Collet Neck die. This combo is very easy on brass. Not only better on brass but the added benefit of little to no runout.

January 22, 2023, 01:51 PM	#18
tangolima Senior Member Join Date: September 28, 2013 Posts: 3,816	It is during extraction/ejection rather. The ejector keeps a strong bias on the brass head. As soon as the mouth clears the chamber, it starts to tilt towards the ejection port, dragging itself on the teeth of lugs. If the bolt goes fast, it won't has time to tilt enough. -TL Sent from my SM-N960U using Tapatalk

January 22, 2023, 03:27 PM	#19
Metal god Senior Member Join Date: April 10, 2012 Location: San Diego CA Posts: 6,875	I had some feed ramps doing that . I took some small files to the edges . I assume I don’t need to say don’t get to happy with the files ;-) __________________ If Jesus had a gun , he'd probably still be alive ! I almost always write my posts regardless of content in a jovial manor and intent . If that's not how you took it , please try again .

January 22, 2023, 03:38 PM	#20
tangolima Senior Member Join Date: September 28, 2013 Posts: 3,816	I may do the same after identifying the guilty teeth. I guess I just to smooth them a bit. Not going to touch the bearing surface for the lockup. -TL Sent from my SM-N960U using Tapatalk

January 22, 2023, 06:41 PM	#22
tangolima Senior Member Join Date: September 28, 2013 Posts: 3,816	I was thinking about increasing the gasing a little. Loading the load hotter, using a slower powder etc. I am not really desperate to resolve the issue. Mostly it is driven by curiosity. BTW, I have put about 1k rounds through this rifle. Cleaned it only twice. It is a cheap A2. Once a while I can shoot better than 1moa 10-round groups with its peep sight. But l found it less and less frequent. For the heck of it, I put a sub-$100 lpvo scope on it. Now that sort of groups becomes routine. It is my failing eyesight. No fun getting old. More funds on optics. -TL Sent from my SM-N960U using Tapatalk