Flattened primers acceptable pressure sign?

[Shane Lindsey]

Virgin cases hide pressure. If you are close to max, once you reload the fire formed cases (which looks like you have here) it becomes more apparent. You velocity probably increased as well from the virgin cases.

I get swipe on cases also without firing them. Tight spring, rough ejector, blah, blah. I always chamber an unfired case and remove without firing to get a sample. I typically look for the ( ) and then know that is my max, max. An animal won't know the difference...

 

[QuietTexan]

Looks like you have a faint ejector print ( ) and some swipe

I get swipe on cases also without firing them. Tight spring, rough ejector, blah, blah.

Interesting. I'll defer to you since you have the first hand experience, but my first reaction was that the primer was not to only pressure sign in the picture. I've seen primers that flat from relatively mild/ factory loads before, but the combination of the swipe made me pucker a bit.

 

[26Reload]

Something over looked here is shooting temperature....was it hot while shooting...did you keep the barrel cool and the ammo cool...
I try to shoot between 55-70...about the temps I will be in the desert....
But knowing if I head north it will mostly likely be freezing with snow....

 

[RidgeRebel]

It was approximately 90 degrees

 

[ShtrRdy]

Federal primers are generally a softer cup which looks like its flattening more.

Looking at the SAAMI spec it shows a 160 grain going 2950 so I'd say you were in the ball park.

 

[Hard rock]

Something over looked here is shooting temperature....was it hot while shooting...did you keep the barrel cool and the ammo cool...
I try to shoot between 55-70...about the temps I will be in the desert....
But knowing if I head north it will mostly likely be freezing with snow....

Back off .5 grs at a time and see where things go south and work back up you might still maintain good vel acc etc at 1 gr or so less powder also back off on your full length resizing a bit and leave a little tighter headspace if that load shoots really good I would tweak it with a little less powder when it cools down just be careful

 

[26Reload]

Been watching some of Cortinas reloading shows...
Didn't see the one I'm thinking of...but he has a winter load and a summer load...
You might be in a winter load...but I don't recall how much he said to reduce powder to mitigate the heat...
You might try to find reference to that.....
But if headspace is good like Hard rock is thinking...and soft primers..you could be at the max of your rifle...or slightly above...

 

[Glenn Tullius]

Doesn't bother me, IF the bolt opens freely and the brass comes out freely. You will no doubt be trimming brass soon though.... and I would expect a possibly shorter brass life.

 

[gvjm]

Hey fellas,

I know flat primers are a sign of pressure, but I was wondering if flat primers that are not cratered and have no leakage around them are acceptable. I am loading a 7mm Saum with ADG brass, Berger 180 hybrids, Hodgdon 4831sc, and Federal Gold Medal 210 primers. I worked up to a load of 60.7 grains that shoots one hole groups with an ES of 11 FPS for five rounds. I am super happy about the performance, but the primers are pretty flat and I am a little concerned I may be pushing it too hot. I am right at 2855 - 2866 fps which also right what I was shooting for. So my question is: safe to run? or find a lower node?
Thanks

Bob

I've seen flattened primers on my factory as well as my handloads with my 7 mag. I think a certain level of flattening is to be expected with magnum loads.

 

[Stan Malinky]

Quick question, did you notice if the primers were high when you seated them?

 

[jjmp]

looks to hot from where I'm sitting, you mentioned 90 degrees, I've runed new strong brass shooting in 85 degrees heat no more of that lesson learned,if you have a good reload you know it because the rifle shows you ,no offense meant just have fun and be safe . This is where a chronograph sure helps , but didn't read every post . Someone mentioned summer reloads VS winter reloads this again is very important to study depending on where you live . Cheers!!!

 

[Frank in the Laurels]

There usually a great sign that enough is enough...game's not wearing body armor in our area...

 

[Flintlock shooter]

A slightly lighter powder charge may not really change your MV/SD/ES but will make your brass live longer.

 

[30BR]

I'd mike the OD at the case head, and compare it to unfired brass... more than .001 oversize and I'd toss it.