Extruded primers safe to shoot?

This is what I expected when the picture posted.

While it's called a 'Crater' in 'Common' terms...
More accurately it would called a 'Donut' around the firing pin strike.
('Craters' don't always have a raised rim around them)

The actual scientific/industry term is 'Extrusion'.
Extrusion is a pressure/die forming process (in most cases) while a 'Crater' is a depression.
The firing pin strike is a 'Crater' (depression).

Amp44 hit the head on the nail.
CCI 400 is a fairly soft primer cup material, so I see donuts with them also using loads that show no other pressure signs, using loads that are well under the maximum 'Safe Published' powder charge weights.

Since the cups don't fail (like a small pistol primer cup might under the same pressure) I don't see any reason to worry about it too much.

I wouldn't give it a second thought at all if it were a safe published charge weight, but fired through a military clone rifle or a 'Lesser' quality rifle.
This is what AMP44 was getting at, military clones and lesser quality rifles OFTEN have oversized firing pin HOLES in the bolt, and softer primers will EXTRUDE into that gap/void without failure.

Military rifles were traditionally less than 'Tight' in machining terms.
While the US military has exacting standards, there has been some real JUNK produced in other parts of the world, and cloned rifles for the civilian market have about ZERO standards.

To this end, military primers are VERY hard, which often leads to inconstancy in ignition, and the reason consistency shooters don't seek out military primers, even though they are available both new manufacture & surplus market.

Personal observations,
I find CCI 400 to be consistent feeding due to their consistent sizing.
I find them to be consistent in ignition, allowing for velocity (FPS) strings to be under 10 FPS at times, all else being equal.
I find variations in string velocities to be small even with aged or mixed batch/lot numbers, they seem to stay consistent for me.
I don't find vairation from humidity changes when the ammo is loaded, but then again, I do pay attention to relative humidity when preparing to load ammo.

I usually load on a high volume progressive machine, and I find CCI in general, 400 in specific to feed nearly flawlessly.

The common CCI 400 primers quite nearly match bench rest primer results, so like Hornady bullets, I would recommend them since they work as advertised.
 
Well, just a follow up. I pulled some of the bullets to verify powder charges, and triple checked my seating depth, all good. Found a box of Feferal match primers, and the primers look perfectly normal again after firing. Strange indeed. I think I'll pull the ones I've got and start over on them and just use the CCI primers for something else. Unless anyone strongly objects and thinks they are fine to shoot?
 
Some people were asking about my loads. 26 grain Barnes Varmint Grenade over 28.5 grains of W748. Hornady brass. (got this load data from Barnes website.)
 
IF all you've got left is 20rnds or less loaded, I'd shoot them up and not worry about it. OR pull the bullets, dump the powder back in the can and then work up NEW loads using the CCI primers.

what you have discovered is one of the results you get when you change a component without working up a new load with it. USUALLY it doesn't result in a drastically unsafe condition, but it could, if the stars line up, just right.

Change the primer, the case, or the bullet and you should drop the powder charge back and carefully work back up until you get pressure signs, see the result you wanted (accuracy, usually) or hit the listed maximum from the bullet maker.

Do anything else and you're completely on your own. This does not mean your gun will blow up if you go .1 over some listed max, it just means that when you go beyond tested data, you're "off the map" and "there be dragons here!!". If a dragon bites you, its your fault.
 
I'll ditto the above. It could be the primer cups are thinner (this reference says CCI 400 have 0.020" thick cups, while Federals are 0.0225", or about 10% thicker, but primer makers change things all the time so its hard to know if it still applies), but I suspect the problem is also that these primers are hotter than Federal 205's. Charles Petty published a test in Handloader around 2006 that showed exactly this issue, but in .223 Remington. Using the same bullet and charge of Reloader 10X, he got anywhere from 3150 to 3300 fps out of different primers, and Federal 205's got the lowest velocity (least pressure) of any in his tests. So you probably needed to knock your load down some for the CCI's.
 
High pressure is further suspected since the CCI primers used with the .204 rounds, assuming they are cratered like the .243 primers, have harder primer cups than most other primers.
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The CCI #400 are NOT harder. The #450 and #41, both SR, are thicker. I stopped using #400's because they do show this deformation and sometimes piercing in warmish 223 loads.
 
Fnusa,

I meant to include that a velocity test would confirm the pressure element of the issue (faster means higher pressure). If it's not happening with your powder, then it is just the thinner cup. As to danger, the only one is that a primer might pierce at its crater rim and gas cut a small pit into your bolt face, but it is unlikely any major damage would occur. Also, you said your fingernail was barely finding the crater, unlike the photo which is pretty strong cratering. If yours is much less, I doubt even the piercing will occur.
 
This one was sure all over the place . First ,if I'm reading it right his primers aren't seating as condor bravo stated , so clean or uniform the pockets . I also thought CCI Primers were harder , I use CCI LR BR-2 primers and never had a problem . The picture of the fired primer looks to me like a pressure problem , but to answer his question , are they safe to shoot ? I wouldn't say yes . Would like to know his case prep procedure .
 
No, he's objecting to the cratering around the firing pin indentation, which he can feel by scraping his fingernail over the bottom of the fired primer. That's why he put up the photo he did. He's got no problem seating the primer initially.

In primer-speak, "harder" often just means harder to ignite rather than mechanically harder (though the two can go together). In the case of CCI, the small rifle magnum primers have thicker cups than their small rifle standard primers (see the reference I linked to).
 
It still sounds like the OP is referring to a situation prior to firing the rounds (safe to shoot?) suggesting high primers, and that the cratered primers developed as a follow up concern. At any rate was not made clear and he did not refute the high primer possibility. With High Primers I would shoot them by closing the bolt very gently just to make sure the bolt doesn't act like a firing pin if closed with excessive force.
 
Extruded primers safe to shoot ? As the pictured extruded then you could use the as a snap cap but as the question I would agree with condor bravo . More like a seating problem . Sorry , nobody likes a smart ass .
 
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"Are these safe to shoot?" referring to primer condition of fired primers, means he already fired some and wanted to know if he can continue, safely with the load and remaining handloads.
Click to expand...

This is also what I got out of his posts. He changed primers, shot some, and got something he wasn't used to seeing, didn't know the correct name for it, and couldn't post a picture of it. Then he found a picture of something like it, that he could post as an example (the cratered primer .243 case) not the actual cases he has.

He's asking if the remaining rounds in that batch are safe to shoot, meaning would they damage him, or his gun. He could have been a bit more explicit, perhaps, but it seems clear enough to me.
 
44 AMP
Now that we figured out what he meant , are the safe to shoot. I don't think he should take the chance . He could reuse the powder .

Chris
 
fnsua said:
Found a box of Federal match primers, and the primers look perfectly normal again after firing. Strange indeed. I think I'll pull the ones I've got and start over on them and just use the CCI primers for something else.
Click to expand...

From that sentence, it is clear it's not a priming problem but appearance after firing, so we have indeed resolved what he meant.

Without a photo of his primers, it is very hard to tell if they are safe (for the bolt face) to fire. When he said he could just feel the crater with his fingernail it sounded like the cratering is much less pronounced than in the photo example he found to share, in which case they are probably OK to fire. If the cratering were as pronounced as in the photo example, then I would suggest pulling the rounds down because that crater is sharp enough that some primers can be expected to pierce and gas-cut little pits into the bolt face at the edge of the firing pin tunnel. There's no physical danger to the shooter, but if he pits the edge of the firing pin tunnel enough. he can expect to start seeing those pits mirrored in other primers in the future, even when the pressure is within the primer's range of tolerance. That just makes it harder to tell when the primer is really at its limit.
 
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