Slightly flattened primer a bad thing?

Klondiker

Klondiker

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I loaded up some .308 with 44.2 gr of IMR4064 and a 168gr Sierra HPBTM and noticed that the primers are lightly flattened. Not totallay flattened where it fills the pocket entirely, but the edges of the primer aren't as round as they were originally.

The firing pin indent isn't cratered at all, and looks as normal as any other fired brass with lighter loads.

Would this be considered an unsafe load? Also there was no problem ejecting spent brass.

Thanks for the help.
 
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You might want to back the powder charge off for a little built in safety. I'm sure they'd be fine cause you're not pounding the bolt open with a 2x4, but you never know. They might be worse on a +30 day in the summer.
 
To expand on what 308bar said. Assuming that your powder charge is correct and your seating depth is saami spec, the material the primer cup is made of could be what what you see. You may also look for a smear from the extractor.
Check the articles/pictures on the internet. There are lots of different pictures posted to see different results from excess pressures.
 
Primers that are a little bit flat should not be a problem. I would only worry if you were getting flat primers in conjunction with some other pressure sign.
 
Sounds safe to me. As 308bar said if your useing fed primers they always flatten out, I use them in my 308 and get primer flattening at 42.5gns of varget, so if the bolt opens fine and there is no other Pressure signs I wouldn't worry about it
 
I'm with everyone else ... sounds like either soft primers, or you are just getting to the upper end of Safe. If it was me, I'd back the powder off maybe 0.5 gr and see if the groups hold the same.

Until you see some visible cratering, or serious falttening of the primers, you shoudl be safe - and if you have no other signs of pressure (sticky bolt, swollen cases, etc..) yet, I'd say you are good to go.
 
This post shows exactly why looking at how flat a primer is, is a useless way of judging pressure.
Every body has their own idea of what flat is. By the description the OP gave, I would say it is a light load.
your 308 Winchester was designed to operate with some 55,000 pounds, or so, of pressure, to drive the bullet at it's designed rate of speed. Don't you think that amount of pressure will flatten the primers?
In other words, the normal pressure the cartridge was designed for will, of course, flatten the primer. Just as factory loads flatten the primer.
It seems to be a given that Federal primers are softer, thus flatten more with the same load, while other brands are harder.
If I get around to it I will load the same load with several different types of primers, shoot them, photograph the primers and post the picture to let you guys figure out what the primers were.
 
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