pancaked primer pic wanted

okie24 · July 21, 2012, 09:06 AM

Could someone please post a picture of a flattened primer.

Lost Sheep · July 21, 2012, 12:41 PM

Welcome to the forum and thanks for asking our advice. It is good to have understanding of how your firearm works and what happens when it does not work optimally. I don't want to discourage you from posting questions, but this, I think, is the best (most complete) answer I can give.

Go to the web site

https://www.google.com

and type in the phrase

flattened primer

you will find dozens of pictures and a bunch of explanations, too.

Lost Sheep

jepp2 · July 21, 2012, 02:51 PM

You didn't state why you were interested, but I will assume it was for pressure indication.

My experience is that flattened primers can be a better indication of headspace than pressure. But I will provide the following picture to show fired cartridges with increasing pressure. Note the increased cratering and on the far right side case you can see the ejector mark.

mohr308 · July 21, 2012, 07:01 PM

out of the rounds in this photo, which is the one that is borderline bad or are all of them bad?

jepp2 · July 21, 2012, 08:17 PM

Quote:

out of the rounds in this photo, which is the one that is borderline bad or are all of them bad?

I didn't fire them so it makes it very difficult to answer that. The first two on the left, show primers that appear to still be rounded normally or almost so. The middle round and the right hand two definitely show indications of primer cratering and ejector marks.

The best resource I have found listing the most comprehensive list can be found here.

Learning what you are shooting and noticing changes from the list are what I find to be most useful. On bolt action rifles and revolvers I almost always notice changes in extraction when I begin to see evidence of high pressure. But I am very careful in sizing so I don't tend to get flat primers from excessive headspace.

mohr308 · July 21, 2012, 10:34 PM

I guess what I mean is if the only sign of pressure was just in the primer, what would be the one where if I saw it I should be cautious?

Brian Pfleuger · July 21, 2012, 10:46 PM

Pressure signs?

UncleNick keeps a thorough list...

http://www.shootersforum.com/handloa...ure-signs.html

Problem with primers is that they're all different. I have used 3 different primer types (2 brands) in 357sig. One will pierce and crater on even the weakest (below starting) loads, another mushrooms at starting loads and the other (CCI) looks exactly the same from starting loads to healthy, over book max loads.

July 21, 2012, 09:06 AM	#1
okie24 Member Join Date: March 31, 2012 Location: Southern Oklahoma Posts: 55	pancaked primer pic wanted Could someone please post a picture of a flattened primer.

July 21, 2012, 12:41 PM	#2
Lost Sheep Senior Member Join Date: January 24, 2009 Location: Anchorage Alaska Posts: 3,341	Do you have internet access? Welcome to the forum and thanks for asking our advice. It is good to have understanding of how your firearm works and what happens when it does not work optimally. I don't want to discourage you from posting questions, but this, I think, is the best (most complete) answer I can give. Go to the web site https://www.google.com and type in the phrase flattened primer you will find dozens of pictures and a bunch of explanations, too. Lost Sheep

July 21, 2012, 02:51 PM	#3
jepp2 Senior Member Join Date: December 24, 2008 Location: Loveland, CO Posts: 1,476	You didn't state why you were interested, but I will assume it was for pressure indication. My experience is that flattened primers can be a better indication of headspace than pressure. But I will provide the following picture to show fired cartridges with increasing pressure. Note the increased cratering and on the far right side case you can see the ejector mark.

July 21, 2012, 07:01 PM	#4
mohr308 Senior Member Join Date: January 15, 2012 Location: Western New York Posts: 466	out of the rounds in this photo, which is the one that is borderline bad or are all of them bad?

July 21, 2012, 10:34 PM	#6
mohr308 Senior Member Join Date: January 15, 2012 Location: Western New York Posts: 466	I guess what I mean is if the only sign of pressure was just in the primer, what would be the one where if I saw it I should be cautious?

July 21, 2012, 10:46 PM	#7
Brian Pfleuger Moderator Emeritus Join Date: June 25, 2008 Location: Austin, CO Posts: 19,578	Pressure signs? UncleNick keeps a thorough list... http://www.shootersforum.com/handloa...ure-signs.html Problem with primers is that they're all different. I have used 3 different primer types (2 brands) in 357sig. One will pierce and crater on even the weakest (below starting) loads, another mushrooms at starting loads and the other (CCI) looks exactly the same from starting loads to healthy, over book max loads.