Cracked mouth

Cerdan

Cerdan

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I was reloading the other night and caught sight of a tiny crack, 1.5mm long max, at the mouth of one of my casings. Got me thinking: How dangerous is this?

I can understand how case head separation compromises the whole pressure seal of the chamber, but in trying to visualize what would happen upon firing a case with a slight crack in the mouth, I couldn't see how it would pose a problem. The case would expand, but it would meet the chamber before the crack got a chance to widen much; it seems to me the seal would stay intact... Am I wrong?
 
I would throw it out right away. Brass is cheap.

Some guys suggest 4 reloads per case, I push that a bit. But when it comes to a compromised component.. its in the garbage instantly.
 
Not dangerous, but you'll have inconsistent neck tension which affects accuracy so chuck it. Good that you're inspecting your brass closely.
 
Number of reloads per case is very caliber/brass quality dependant.

I don't know why you would ever use a cracked case, but I do know of a guy that uses cracked 45ACP brass regularily with no issues.
 
I'm talking about bottle neck rifle cases. If they are properly reloaded and without excessively heavy loads, the normal way for them to wear out is for the necks to crack. This is why people who want to extend the life of their brass will anneal the necks. After about ten or twelve loadings the necks can be annealed and they may be good for another ten loadings. How many times they can be reloaded varies greatly by the rifle they are fired in. If the rifle has a larger chamber at the neck, the case neck will expand more, meaning it will be pushed in more in sizing, so of course it won't last as long as will cases fired in a tighter chamber.
A split neck is usually noticed by weaker pressure required in pulling the expander through the neck. Sometimes it is just a mark where it is going to split. In this case I usaually load it, knowing that will be the last loading. If the cartridge was to be used in a shooting match, no, I would not load it, because as someone has said, it may shoot SLIGHTLY different from the rest, due to less pressure on the bullet. If the bullet is seated to touch the lands, then this last remark can be ignored.
I see no danger whatsoever, in shooting a case with a cracked neck, as long as the bullet isn't so loose that it will come out prematurely. Indeed, I've seen cracked necks in older factory ammunition that was never fired. I have never heard of these being thrown away without shooting them.
 
Sorry, I don't get your meaning, -- "where do you think the crack came from?"
I think I explained that cracks in the neck are the normal way that cases wear out. As I said, sometimes a mark, lengthwise on the neck, can be seen where the neck will crack, usually on the next firing.
 
I was replying to Cerdan. The case cracked the last time he fired it. There were no ill effects. If he had not noticed it and fired it again, he would still not likely notice any problems. Eventually the neck would fail to hold the bullet in place, it could get pushed into the case under recoil from another round. THEN he might notice a problem.....

Trash it. Tiny cracks will not remain tiny cracks. But if you missed it, nothing would happen while it was still a tiny crack.
 
Thanks everyone. You've pretty much confirmed my hunch.

I ended up firing this one yesterday out of curiosity, but from now on I'll chuck anything that's compromised in the slightest.
 
Neck cracks will not be dangerous. I do remember someone claiming that they may lead to flame erosion of your chamber if they happen often enough, as jets of flame exit the crack and impinge on the chamber walls.

H4831 said:
This is why people who want to extend the life of their brass will anneal the necks. After about ten or twelve loadings the necks can be annealed and they may be good for another ten loadings.
Click to expand...

Holy smokes, I need to find out what kind of brass these people are using. My cases crack at the neck generally on the fourth loading if not annealed.
 
Hey!!!!
Case life is very variable.
Some of the factors are --
caliber
how close to max loads you are loading
brass manufacturer
do you neck size or full length each time
and a few others

My cases last up to 50 odd reloads... in 22-250. Average life is around 35 reloads (without annealing).
In 223 I have yet to have a case failure.

Cheers
 
H4831 is exactly right. you need to anneal your cases. when I find cases hard to pull out over the expander ball when being resized, it is time to aneal them. this will help to prevent them from cracking at the neck because it makes the brass softer.
:cool:
 
I like hearing peoples' thoughts on this because I see lots of tiny mouth cracks and deal with them in a way I think is quite safe. But I'm new to this so what the hell do I know... :redface:

I see cracks either post-cleaning inspection or else in the press itself, right after the belling stage. (I wonder if this isn't the most significant stress of all... I may reel in my bell slightly especially for plated or jacketed bullets.)

Anyways, if I eye them to be 1-2 mm, I sometimes let them go. And I fully expect they will have doubled in size on the next cycle so that will be their last loading.

In my first 3,500 loads... that was 500 cases, used fairly equally, so call it 7 reloads each... I've thrown out 40 cases due to mouth cracks so far. I expect they'll start to fail more frequently now so I picked up 1,000 more to cycle through separately. Very few throw-outs due to head pre-separation symptoms (e.g. bright/different colored ring or bulge) but that's the problem I'm much more aware of and concerned about. I should mention... I'm loading .357 Magnum and a variety of target to major loads but nothing crazy.
 
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