Flattened primers acceptable pressure sign?

RidgeRebel

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Feb 6, 2011
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107
Update

So I ran a few different ladder tests lowering the powder charge by 2 grains. Unfortunately I don't get small velocity spreads without going at least a grain lower in charge. I found a decent node at 59.5 grains. I fired a five round group and found that even with the rounded primers now my rifle still shows a faint ejector mark but the bolt lift was slightly easier.
20210925_095752.jpg
 

RidgeRebel

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Feb 6, 2011
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107
This was with new brass ran through the fl sizer. I know a few mentioned neck sizing but I don't have a neck size die yet.
Thanks for all the replies. By the way here is the current velocity. Not what I was hoping for but it will work.
20210925_095243.jpg
 

Shane Lindsey

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If you are getting pressure with virgin cases, you most definitely will see it with fire formed cases if using the same charge.
you have a pretty good ejector print an swipe on the cases in this picture.

I wonder how a slower burning powder might do. If you have it, maybe give it a shot.
 

Longtine88

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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
Do you have any other powder? 4831 is great but the 7 saum and 180’s loves RL26, RL 23, N565, N560. I use RL 26 in my two. I’m not going to post my load because of the criticism but I’m getting 100 fps faster than you, no pressure signs, new adg brass, With low es/sd’s. Yes that’s fast for a 7 saum fast barrel I guess. And I shot it at 1,000 yards Thursday and temps in the 80's. Your barrel will probably speed up some also so keep that in mind. Mine gained 80 fps finally.
 
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Muddyboots

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The primer has rounded edges but is flattened quite a bit with slight swipe mark. Just looks like to me on razor edge of serious pressure. Pressure on brass is not just an indicator the brass is showing pressure but is also showing your rifle is possibly in a danger zone for the pressure the cartridge is rated for by SAAMI. There is no such thing "my rifle can take it" when dealing with obvious sign of pressure on brass. Max loads cannot be assumed to be doable in every rifle. Its just the way it is that each rifle is unique in its build and may not reach book max loads just due to inherent build specifications. Read your brass and realize it ALSO an indicator of pressure safety for the rifle FIRST. This has nothing to do on saving brass but saving "face". This is not a rant against you at all but just a general statement on how brass pressure is ignored for cartridge rated pressure for the rifle.

Like others have suggested, RL26 may not be the right powder for your task. It had shown yo be temp sensitive with pressure swings. Maybe RL23?

I hope this was not perceived as an attack against ANYONE but just a comment on pressure.
 
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Blackdirt Cowboy

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Dec 9, 2018
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Texas
I watch both primers and ejector marks, but don’t consider them to be the end all be all signs of pressure. Most of my rifles are Remington 700s and they are famous for a sloppy firing pin hole. Most all my loads, and even factory rounds will have a cratered primer. Also, as mentioned above, some primers will flatten quicker than others.

I’ve also had several rifles that would leave a significant ejector mark with factory ammo, so if all I’m seeing is a slight ejector mark, I’m ok with that. Sticky bolt lift is another story. That’s dangerous territory. Also, the feel of the recoil is helpful. If you pull the trigger and think, **** that kicked harder than it should have, coupled with any pressure signs, that’s a warning that your a little too hot.
 

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