I think the brass may have gotten brittle.

by Hoot @, Diversityville, Liberal-sota, Wednesday, February 18, 2015, 11:58 (3507 days ago)

I picked up some elder reloads for the 'quiz rifle' below, strictly for the components. Proceeded to disassemble with the impact puller and lost about 1/4 to cracked necks and these three a bit more spectacularly. I'll be annealing the remainder...


[image]

I think the brass may have gotten brittle.

by MR, Wednesday, February 18, 2015, 12:17 (3507 days ago) @ Hoot

The did that with an IMPACT PULLER!?!?!

Holy Moly!

I think the brass may have gotten brittle.

by MS @, Southern Michigan, Wednesday, February 18, 2015, 17:25 (3506 days ago) @ MR

Hoot's been workin' out again it appears!
Or he ate a big can of spinach....

I think the brass may have gotten brittle.

by Cherokee @, Medina, Ohio, Wednesday, February 18, 2015, 17:28 (3506 days ago) @ Hoot

WOW - never would have thought that would happen...

I think the brass may have gotten brittle.

by Murphy @, Wednesday, February 18, 2015, 21:04 (3506 days ago) @ Hoot

Whoa! Now that's different!

Murphy

I think the brass may have gotten brittle.

by CJM @, United States, Thursday, February 19, 2015, 00:43 (3506 days ago) @ Hoot

If the brass is the same age as the gun, could that be caused by mercuric primers? Not normal work-hardening or the brass would have come apart during sizing. I don't think brass normally can get harder and brittle by just sitting, but mercury contamination would get worse as the mercury continued to dissolve into the metal. It might be a good idea to see how brittle the case heads are after annealing, you don't want to find out that they are still brittle by firing them in the gun.

I think CJM has something here...

by Paul ⌂, Thursday, February 19, 2015, 04:50 (3506 days ago) @ CJM

it's been niggling at the back of my brain - that ain't normal work hardening. Hadn't put two and two together, though, like he did. If it's old brass, there's a good chance that it was fired with mercuric primers. In which case, you need new cases.

I think CJM has something here...

by Otony, Thursday, February 19, 2015, 08:41 (3506 days ago) @ Paul

Paul, mercuric primers or not, I KNOW he needs new cases! :-D

Otony

As I do not know the entire history, it's certainly possible

by Hoot @, Diversityville, Liberal-sota, Thursday, February 19, 2015, 11:15 (3506 days ago) @ CJM

The reloading data on the boxes indicate they were loaded in 1970-72. The primers "appear" to be equivalent to modern Winchester and Federal.

The cases are all reformed .30-06, and some brand new, by all appearances. For this particular cartridge, the shoulder is pushed back and the neck reduced. My assumption is either no or ineffective annealing was done at the time of forming.

There is much disagreement around the 'net regarding 'age hardening' of brass and copper alloys. Age hardening is intentionally done for certain alloys but I cannot seem to find if it can be done for cartridge brass. I know for certain that I have seen many instances where loaded ammo shows neck cracks and in every case, said ammo has been loaded and sitting for decades. That said, I have also seen much more ammo which is also decades old with no issues.

At the very least, I will get much needed annealing practice.

Addendum re: Age hardening

by Hoot @, Diversityville, Liberal-sota, Friday, February 20, 2015, 06:07 (3505 days ago) @ Hoot

After much reading, it seems that cartridge brass, Cu-Zn alloy, does not 'age harden'...at least, near as I can 'cipher it. It's mostly the beryllium copper alloys used for springs and electrical contacts. It's properly called precipitation hardening and there's reams of technical data, phase diagrams and whatnot out there in the ether.

This would then leave a couple of possibilities: improper/no annealing or chemical contamination (mercuric primers, ammonia cleaning, etc.). Storage conditions may also be a possibility but that isn't very certain.

The brass all looked in good shape, so no obvious corrosion evidence. There is also no discoloration associated with annealing although that is easily polished off.

FWIW...

Modern ' 06 brass is cheap and plentiful

by mcassill, Thursday, February 19, 2015, 20:52 (3505 days ago) @ Hoot

Just saying.

Yep, I agree.

by Hoot @, Diversityville, Liberal-sota, Friday, February 20, 2015, 05:46 (3505 days ago) @ mcassill

This ammo was acquired with the rifle and I didn't have dies at the time. Considering what was paid, the brass, powder and primers were free.

Now, I have dies and proper headstamped brass from Buffalo Arms so it has been more of a bullet salvage operation than anything.

As mentioned earlier, I need to learn to anneal cases. The 'survivors' will provide much practice.

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