Flattest primer award

[Another_Kelley]

Noticed these after doing a little range pickup... Had to share.

I've never seen part of the primer pocket itself extrude out and flatten against the bolt face like the one on the left. The 'half moon' shaped piece of material you see next to "REM" is actually brass from inside the pocket! The primer on the right has expanded beyond the diameter of a large rifle primer. Not my handy-work by the way

 

[GBExpat]

WHOA!

 

[PapaG]

Another one of those "max loads are just suggestions, l think I will throw a few more grains in. What could it hurt?"

 

[Wreck-n-Crew]

WHOA!

Took the words right out of my mouth!

 

[reddog81]

Impressive. I bet they had to beat that brass out of the chamber with a hammer. You'd think they'd realize something was terribly wrong after the first one.

Those must have been some pretty strong primer to not blow a hole in them.

 

[Doublehelix]

Dang! Now those are what I call flat primers!!!

 

[mdi]

Ummm. Whut's rong wif dem? Yep, I'd say those deserve the award for flattest primers, flattest I've seen...

 

[hdwhit]

Another Kelly wrote:
The 'half moon' shaped piece of material you see next to "REM" is actually brass from inside the pocket!

From the picture, it looks like the silver half-moon shape on the left is part of the primer cup rather than part of the case's primer pocket.

It is common in military brass where the primer crimp is not fully removed for the crimp to catch the mouth of the primer cup and turn it down producing exactly the half-moon shape shown in the photograph. Since I lightly ream rather than swage primer pockets on ex-military brass, this happens to me with 2 or 3 primers out of ever thousand rounds I load. Since it leaves a path for propellant gasses to exit the case upon firing, it is potentially dangerous and one of two things should have been done by whoever reloaded the case:

• the case with mangled primer still in place should have properly been disposed, or
• the mangled primer should have been removed (and properly disposed of), the primer pocket crimp properly removed and the case re-primed.

The fact neither of these things happened means that whoever reloaded these cases was not following proper procedures (or in my opinion even exercising common sense) and I would suggest the cases be discarded.

 

[Another_Kelley]

It is common in military brass where the primer crimp is not fully removed for the crimp to catch the mouth of the primer cup and turn it down producing exactly the half-moon shape shown in the photograph.

That makes good sense. I was wondering how there could be no cratering or ejector swipe to speak of like the one on the right if the pressure was so insane. The picture makes it look like the half-moon shape material is silver, but it's far more brass colored - and aren't primer cups primarily composed of brass?

Definitely not planning on salvaging these, just gotta keep them around as 'award winners' I spose.

 

[WestKentucky]

I've never seen anything close to that kind of pressure. Can you check those jokers for case head separation and see if you have internal signs of issues? I would like to see other views of the cartridges too, just out of curiosity.

 

[JimKirk]

Holy Cow! I seen some flat primers in my days ... but if I was handing out certificates ... those would be at the top of the board !!

 

[FROGO207]

Just when I think that I might possibly have seen it all---THIS!

 

[medalguy]

I have a few similar to those that I have picked up at various places. Things like incipient case separations, .308 shot in a .30-06, 9mm fired out of what looks like a .40. I keep them on a shelf above my reloading bench to remind me to at all times BE CAREFUL! So far I haven't managed to make any of those myself.

 

[Chuck59]

You'd like to think that everybody that has a gun in their hands is thinkin..
Obviously, this isn't true. <shrug>

 

[Walkalong]

From the picture, it looks like the silver half-moon shape on the left is part of the primer cup

Yep.

Those are pretty bad.

 

[JRWhit]

As Bob says to Jimmy," Hey Jimmy, i got these hand loads you got to try. They're loaded the way the 223 was meant to be loaded. You know, before the lawyers got involved. They're not as hot as my hunting loads but they're 10 times better than anything you get off the shelf. Just make sure and take a raw hide hammer with you as they are made to such exact tolerances that If your rifle is just a touch out of spec they'll stick when extracted."

 

[243winxb]

Not pressure related.

Forcing a primer into a GI crimped pocket , looks like that, after firing. I made a few like that in 45 acp, back in my Lee "hammer" classic loader days.

Surplus GI 45 acp ammo was $3 for 50 rounds in the 60s . Shot it just for the brass.

 

[Glockula]

I have found some ugly cases. Those are some real bad ones. I have always been fond of learning from the mistakes of others.

 

[BigBore45]

LOL. Don't have a 22-250 no problem.

 

[Another_Kelley]

I've never seen anything close to that kind of pressure. Can you check those jokers for case head separation and see if you have internal signs of issues? I would like to see other views of the cartridges too, just out of curiosity.

Sry, not trying to ignore ya - I did run a small pick down the inside wall of the cases - and couldn't feel any thin spots.

 

[Another_Kelley]

 

[Arkansas Paul]

I have a few similar to those that I have picked up at various places. Things like incipient case separations, .308 shot in a .30-06, 9mm fired out of what looks like a .40. I keep them on a shelf above my reloading bench to remind me to at all times BE CAREFUL! So far I haven't managed to make any of those myself.

I keep crazy stuff like that that I find too.
I have a piece of 7mm Rem mag brass that's blown out. I'm thinking it was fired in a .300 mag. I bet that group had a helluva flyer. lol

 

[fguffey]

I've never seen part of the primer pocket itself extrude out and flatten against the bolt face like the one on the left.

in my opinion the primers show evidence of the beginning of high pressure. .




And then there is the perceived difficulty in measuring case head expansion; and bladed micrometers and the ability of a reloader to measure anything less than .0005".



F. Guffey

 

[Walkalong]

Before the Internet acceptable case head expansion/upset was .00025" for factory over the counter ammo.

What is it now? The same I assume. You know, ATI. After The Internet, vs BTI, Before The Internet. We should add those to the acronym list.

And while it may be news to you, not every "internet reloader" is incapable of using micrometers.

 

[fguffey]

And then there is the perceived difficulty in measuring case head expansion; and bladed micrometers and the ability of a reloader to measure anything less than .0005".

And while it may be news to you, not every "internet reloader" is incapable of using micrometers.

22 responses without a mention of case head expansion, news to me? When the subject of high pressure is discussed case head expansion/diameter is always omitted.

F. Guffey