If this happens, does it render the case unsafe to use even after resizing? I recently just hit pressure on a load for the first time and noticed it did that on a couple cases. Wondering if I need to toss them out
Flattened primers acceptable pressure sign?
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You should be able to tell if they are hard to push into a case holder. Plus, the manufacturer of the case makes a difference. I am comfortable with loads in Lapua brass that I would never try in Federal or Remington brass. The expansion at the base means the primers will be more likely (not "certain to") get blown out. Because if one loading pushed the bases out, a second load at that pressure will do more "damage", as the head is now not as strong as it once was. Why tempt fate?
FWIW, I fireform my brass twice at lower loadings to harden up that area of the case before pushing them to my max load. My first fireform will be about 300 fps slower, and I try to use the slowest safe powder I have on hand for that ctg. That will not blow the case out fully; cases will still be a couple/3 thou shy of fully formed match brass. The 2nd load is usually only about 100 fps slower, and after that the brass can be F/L resized to yield about 1.5 thou clearance. CAUTION: I'm a TARGET shooter, NOT a hunter. I don't recommend keeping hunting resized brass so tight. .003" I feel is a better field round, and a touch more if using an autoloader.
I find I get better life out of the cases when I don't push them to within an inch of their life on the first firing.
X2!
I'm not seeing any ejector marks, that's a good thing. If the bolt lift is clean and easy and you're not seeing any case head separation, i'd say it's okay.
Sure is a tough decision on a load that shoots that good.
Shane Lindsey
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That don't look like an ejector to you?
Hugnot
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Pressure is what drives the bullet thru the barrel & there will always be signs of it. Excessive pressure is not welcome and might occur from any number of causes and be shown in different ways. I look for difficult bolt lifts, leaking primers, expanded primer pockets, case head swipe marks, imprints of ejector slots & ejectors, Yes, I sure look at my primers & use a 10X Hasting Triplet (fancy name for small magnifier) to look for primers with no radii (assuming correct head-space), cratered primers with tight bolt face holes, or leaking primers and any number of other things. Excessive pressure can blow the primer out of the primer pocket. I also have a 6.5X47 Lapua (super hard brass head & small primer pocket) and think what are acceptable pressures for it would probably cause problems with other cartridges.
The pics shown above are probably what most max loads show - minor scuffing, flattened primer, no cratering and no leaking. Good pics!
Get one of those little magnifiers & get a good detailed look at stuff.
The pics shown above are probably what most max loads show - minor scuffing, flattened primer, no cratering and no leaking. Good pics!
Get one of those little magnifiers & get a good detailed look at stuff.
Your post in #14 signifies what you already know, and why you posted the OP, your gut feeling is that it's too hot.
Trust your instincts.
I don't load for SAUM or use 4831SC, but looking at load tables, your velocity for the 180s seems that you are approximately at max load. Look for a node below that. Anyone with Quick load who can help him?
Once you drop in temp, this may be a perfect load.
Out of curiosity, it'd be an interesting test to run it with standard LR primers to see if your pressure changes and what it does with your accuracy.
From your OP, your primer cup shows flattening, nothing that I would worry about in my rifles. When I see the primer cratering, and / or feel sticky or heavy bolt lift, I know I'm over. Shoot a rifle enough, you can also tell with the recoil whether you're running hot.
Trust your instincts.
I don't load for SAUM or use 4831SC, but looking at load tables, your velocity for the 180s seems that you are approximately at max load. Look for a node below that. Anyone with Quick load who can help him?
Once you drop in temp, this may be a perfect load.
Out of curiosity, it'd be an interesting test to run it with standard LR primers to see if your pressure changes and what it does with your accuracy.
From your OP, your primer cup shows flattening, nothing that I would worry about in my rifles. When I see the primer cratering, and / or feel sticky or heavy bolt lift, I know I'm over. Shoot a rifle enough, you can also tell with the recoil whether you're running hot.
Hot round. Back off powder charge. Maybe some more freebore if your close to the lands to relieve pressure. Either way it's a little Hot. Thing is your stressing your gun with possible over pressure and it's not worth the risk. Soft brass can fool a person sometimes but flat primer like that in my experience is a good sigh of being hot. Either way play it safe. Not worth an extra 50 FPS
also check your overall brass length. Ensure sammi length. If long you could be pinching your bullet when action is closed.
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Have you tried neck sizing, as mentioned above you may have a little excessive headspace slamming the brass, neck sizing would eliminate that issue.
Calvin45
Well-Known Member
Agreed. Again, Winchester super x powerpoints factory ammo always pancaked primers and gave ejector swipes back when I shot Factory ammo. Certainly wasn't dangerous.
I recently worked up a no doubt very hot load for my .300 win mag (there's a thread about it, got a hbn treated 120 Barnes tac tx to 4050 feet per second, Peterson brass, superformance powder, happy dancing all around) no stiff bolt lift, easy "one finger" bolt operation and extraction, no cratering, tight pockets, and using my calipers to measure everything and finding the cases had not discernibly lengthened at all or expanded at the web are all the things I'm reassured about to continue shooting the load
Gamesniper19
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You are on the edge of too hot. Slight pressure signs are not always bad if you are meaning to run them at the top of your accuracy node. If you are going to hunt with it and you want every bit of velocity you can get and you aren't getting a sticky bolt or other issues with being on the ragged edge - run it
If you are worried about shooting in high temps >90 degrees, adding a suppressor, or want max brass and barrel life, dropping out of pressure with 1/2 to 1-1/2 grains less powder probably wont take you out of your accuracy node and will alleviate any long term issues
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Plinker147
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I had a rifle that I could only get good accuracy when it had slight pressure signs, about identical to what OP is showing. I hunted with that load for a few years without issue. A flat primer, and slight ejector marks are signs of pressure. It doesn't tell you how far from safe you are. In that same rifle I could load another full grain of powder and the pressure signs didn't change(visibly) I have middle the road load's that show ejector marks on cases all the time. It doesn't mean they are unsafe just shows signs of being fired with X amount of pressure.
Reading pressure is a total of all signs, flattening primers, sticky bolt (probably best indicator) and deep ejector marks, excessive brass stretching, short brass life than you would expect. You need to pay attention to all signs.
The problem with operating with the pressure signs is its always in the back of your mind wondering is it hotter today than when i normally shoot, did i make a slight mistake reloading and I'm half gr hotter? Its best not to put yourself in those situations and rework you load to find the accuracy without pressure signs. 50fps means nothing on a bigger scale. That's my 2 pennies on the subject
Reading pressure is a total of all signs, flattening primers, sticky bolt (probably best indicator) and deep ejector marks, excessive brass stretching, short brass life than you would expect. You need to pay attention to all signs.
The problem with operating with the pressure signs is its always in the back of your mind wondering is it hotter today than when i normally shoot, did i make a slight mistake reloading and I'm half gr hotter? Its best not to put yourself in those situations and rework you load to find the accuracy without pressure signs. 50fps means nothing on a bigger scale. That's my 2 pennies on the subject
Mike Matteson
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That flatting of the primers look about right to me. That where I stop at. Setting your shoulder bump and not totally going back to SMMA Length will help in case life. Primer pocket is where it will end the case life. I came across a possible way to length that life of the primer pocket, but haven't applied it yet. Annealing the case at lease every third firing or every time. It's a work of love, and accuracies that is my goal. Velocity plays a big part into it also. If I can't get the group at about 1/2" at a 100yd, and velocity @ 3200fps or above, I am not interested in it. Others have different ideas and that fine too. It's want you want and safe is what counts.
