Brass splitting at neck/shoulder. Lots of pics.

[fishwater]

I need some help please.

I have not been reloading that long, but I have reloaded for several different calibers and have a good grasp on things I think. This has never happened before!

The rifle in question is my Mark V .30-378. It is unmodified, except for a trigger job and a B&C stock. It gets cleaned regularly. It came with about 40 brass, some of which were never fired factory rounds, and some that had been loaded once or twice. The rifle has not had much use, and should have a pretty low round count..

The brass:
I have never annealed them.
I do not have a tumbler, I just use compressed air to clean the insides.
Yes, I lube the cases, and brush the insides of the neck.
They have never been neck turned as I do not have one.
I just use basic full length RCBS dies.

These were loaded with 117.5 Gr. of US869 behind a 200 Gr. Barnes LRX. CCI 250 primers.
Length is slightly longer than factory spec, but they are still 0.4" off the lands.
Factory 26" barrel, and velocities are around 3165

These have only been fired 2 or 3 times (different load with 175 gr. barnes.)

At the moment every single case with this new load is coming out of the chamber with a crack at the shoulder/neck. I have already ruined about 15 brass because the bolt opens easy still and I didn't notice it right away..

I would like your opinions on what you guys think is causing this. I am a little confused, because there are no other pressure signs, the bolt opens just fine, it is not even the least bit sticky. These spent brass go into the chamber fine still, and are not tight. The primers look ok (to me.) All measurements I have taken on the cases (loaded and fired) seem to be within spec.



























I am currently in the process of pulling all my bullets apart, and I plan to anneal them all and start over, possibly with a different powder.

I know these loads are hot, but according to Hodgdons I am 1/2 Gr. off max still.

Are these just too hot? Or, is there maybe some other factors at work here?

I crushed the necks on some of these with pliers and they were really brittle.

Thanks in advance.

 

[acloco]

Brass is work hardened.

Buy new brass. If some are like this visibly, the remainder of the brass is not far behind.

Why chance yourself to some brittle brass making a bad day for you??


It is interesting that the vertical split is at or very near the same location on all of them.

Might consider putting a bore scope in this chamber.

 

[fishwater]

Yeah, this brass is definitely not getting used again.
It just came out of the chamber like this and is immediately going in the garbage.

I have never annealed brass before so this is a real eye opener.

I recently discovered the "plier test."

I pinched the necks on a few of these with a pair of pliers and they were mega brittle. They cracked almost immediately.

A few even developed cracks just going through the bullet puller!

All this brass looked fine before being loaded, it just freaked me out that it all started failing at once and I started to question my reloading job. I realize now it was definitely old/brittle brass.

Thanks for the reply.

 

[SidecarFlip]

Don't throw it in the garbage, start a scrap case box and when it gets full, scrap it. A coffee can full will get you and the missus a nice steak dinner. Old scarred pills or pills with deformed meplats are good scrap candidates too.

You are a lucky guy. One more time and that stuff would have blown up in your face....

I use needle nose vicegrips myself. Set them to deform a new case mouth so it deforms and springs back, then try a suspect case.

Not going to get into annealing, I have a bench source and there are too many ways (most chancy at best) on You Tube. Lets just say, not enough is as bad as none and too much is a bad day too.

 

[fishwater]

Thanks for the tip on the vice grip technique, sounds like a great way to test them.

I am researching the annealing stuff right now and I agree 100%, it does sound like a pretty touchy process.

I will try a few once I do some more research and get some practice on all of these junk cases, and do the vice grip test and see where that gets me.

Thanks for the reply.

 

[flashhole]

Yes, that brass is way brittle. Annealing may not even help if it's too brittle. When you anneal you don't want to go beyond the top 1" of that big case.

 

[g0rd0]

it has gone beyond annealing. Pull bullets, deprime and deform that stuff and set aside for scrap. You will be suprised how fast you can fill a can of scrap brass and brass has a very good price at the salvagers, here it is $3.75 a pound.
For an earsplittnloudnbanger like that it is well worth your time to learn annealing.
I used to anneal useing a torch but, at the gunclub a member aquired a fancy machine and he charges 3 cents a piece, now I bring my brass to him and when I get it back it is in great shape all consistantly annealed.
And get yourself a trimmer , now they pay off first time around. I have a lyman that I got in the early 80's it is still going strong.

 

[SidecarFlip]

...Only one trimmer for me now, a WFT, plus I made an insert to trim meplats. Quick, very repeatable, 0.003-0.005 differential across any number of cases and around half the price of a lathe type trimmer.

How about a case every 3 seconds.....

 

[fishwater]

You guys are good... lol.

I did attempt my first annealing job last night, nice that I had so much old brass to practice with.

It turned out to be a futile effort. I was doing great, (drill,large socket, coffee can full of water,) and was getting great color/heat on them. They were still failing the plier test even after I finished the process however.

6 seconds, 8, 10,12,18,24, (24 seconds is way to long I know I was just experimenting at this point.) It didn't matter, the brass was toast!

Out of the 25 not-yet split brass that I had, only 7 survived the bullet puller/re-sizing process.

I do have an rcbs case trimmer, it gets used frequently.

Thanks again.

 

[Roicem]

I had this problem with my brass with the RCBS dies. I changed last year to Redding type S-Match bushing dies and don't have the problem anymore.

 

[SidecarFlip]

You guys are good... lol.

I did attempt my first annealing job last night, nice that I had so much old brass to practice with.

It turned out to be a futile effort. I was doing great, (drill,large socket, coffee can full of water,) and was getting great color/heat on them. They were still failing the plier test even after I finished the process however.

6 seconds, 8, 10,12,18,24, (24 seconds is way to long I know I was just experimenting at this point.) It didn't matter, the brass was toast!

Out of the 25 not-yet split brass that I had, only 7 survived the bullet puller/re-sizing process.

I do have an rcbs case trimmer, it gets used frequently.

Thanks again.

Some more advice (on safety and preserving your face and action). Get a a bottle of templac or a temperature sensitive crayon (available at any welding supply store or online) and use it. I don't condone or recommend the torch-socket-drill motor method because dwell time in the flame as well as flame shape and intensity is paramount to a properly annealed case, something you cannot accomplish with consistency, manually.... Don't say you can, I know you can't. Been down that road, thats why I have a Bench Source. You actually have a couple choices, Giraud Machine makes an annealer, Ken Light has one and there is a no-name on Flea-Bay all the time. The Flea-Bay unit looks a bit cobbly but I'm sure it works. Key is dwell time and case rotation and a suitable heat sink to keep the body cool.

I would have pulled the pills on the brass and annealed them, then resize not the other way around but your annealing method is lacking so thats moot anyway.

Of course I'm not you but what I'd do is buy new brass (or factory loads for the first ignition), shoot them 2 times total, pull the primers and coffee can them and get some more and repeat, all while saving up for a mechanized annealer like a Bench Source. That way, you'll have quite a few to anneal and you aren't running the risk of your gun blowing up.

 

[fishwater]

I did in fact bullet pull, anneal, and then resize. Sorry I wasn't more clear on that.

After trying it, I agree, annealing with the "eyeball" method seems pretty touchy.

I am getting new brass, and looking into getting some new dies and/or neck sizing only so I get a little better brass life.

I was shocked that these were as brittle as they were because they had not been shot that much. I guess full length resizing was pretty hard on them.

I will have a look at the units you mentioned, thanks.

 

[westcliffe01]

It sounds like you have a "loose" chamber and between that and full length resizing (too small compared to the chamber) you are having a problem. It is also possible that the brass was never properly annealed at the factory to begin with. I have had split necks on lake city unfired brass, and it was the LR stuff that was issued to the sniper teams...

Buy the best quality brass you can afford, then fire a few rounds and compare before and after measurements to know in what state your chamber is. Once you know, you have to decide whether you have the chamber set back, or modify your die to best match the chamber you have. I thought some die makers offered this service, but of course in recent times production of custom dies was stopped to try to support the demand for reloading equipment.

 

[SidecarFlip]

It sounds like you have a "loose" chamber and between that and full length resizing (too small compared to the chamber) you are having a problem. It is also possible that the brass was never properly annealed at the factory to begin with. I have had split necks on lake city unfired brass, and it was the LR stuff that was issued to the sniper teams...

Buy the best quality brass you can afford, then fire a few rounds and compare before and after measurements to know in what state your chamber is. Once you know, you have to decide whether you have the chamber set back, or modify your die to best match the chamber you have. I thought some die makers offered this service, but of course in recent times production of custom dies was stopped to try to support the demand for reloading equipment.

You aren't telling the whole story. I personally think whoever pulled the pills from those cases, used a pair of pliers and wiggled them out.......

What he needs to do is compare a new, unfired case to a fired new case to ascertain how much it's stretching and where.

I wonder how much his old cases grew between firings.