Need photo's of excessive Pressure indicators

sithlord6512

Beginner
Nov 24, 2008
107
0
Can someone please provide me with photos or links to websites showing good photos of cases/primers showing signs of excessive pressures.

I know what signs to look for (e.g., cratered primer, flattened primer, shiny ring around case in the web area - what's a web - "shiney" part on head caused by brass flowing into ejector, difficult bolt-lift, etc.). However, I'm not sure what some of these indicators would actually look like (i.e., "cratered" primer, shiny ring around "web"). Thanks.
 
A lot of reloading manuals feature these. However


Primers.jpg




primer-pierced.jpg


Primer-normal.jpg


primers%20crop%203.jpg


primer.jpg



copperpressure5x350.jpg









primsmear.jpg
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Ejector marks (shiny raised areas on headstamp)...primers sometimes lie to you, but when you see these...you are way too hot.

125_2547.jpg
 
Here's a few I've collected over the years. First, ever so mildly flattened primers (notice there is no cratering, just tophatting):

270Wby7828primersclose.jpg


Next up, cratered primers:

primerscloseup.jpg


And now, ejector marks:

Caseheadextractormarkscloseup.jpg


I've yet to get a picture of the case I blew out the primer pocket on, but I saved the case (in my little drawer of interesting handloading things I may need a picture of for reference one day.

Just about all the good manuals post pictures of primers and cases that are questionable. Check out the front section from Hornady or Speer, and I think even Nosler has some good info.
 
Thanks very much. Pictures I will add to my library.

Ridgerunner665 - did you stop using these factory loads? I have a box of factory Federal's that are showing the exact same markings on their case heads. I thought the bolt seemed harder to lift after firing , but because the rounds were factory, I thought they had to be safe (only shot five or these rounds - just started breaking-in the rifle). Should I stop firing rest of the box?
 
Sometimes a new barrel will cause signs of excessive pressure...did you clean it good before shooting it?

I pulled the bullets on the Federal rounds and whacked the Hornady's a couple of times in the bullet puller (seated them longer...they were OK after that)
 
Ridgerunner665,

Yes, I made sure the barrel was immaculately clean - used Hoppe's 9 + Tipton Rod with Jag, then bronze brush, then jag again until patches came out clean - patches no longer "grey" (I was surprised how many times I had to repeat the cleaning cycle given that this rifle was new). I then used Birchwood casy gun scrubber to remove any traces of Hoppe's 9. Finally, as an experiment, I tried my new Outers Foul Out III electrochemical bore cleaner. I expected the rod included with this system would come out clean. Therefore, I was surprised to find the system indicated that it was "cleaning". At the end of the cleaning, the cleaning rod included had a thin layer of copper on it. I was incensed thinking that I was sold a used gun that was passed off as new. I then proceeded to contact Remington, and they said not to worry - barrels are test fired at the factory and that it was not uncommon to have copper fouling in the barrel in even "new" factory rifles.

Sorry, I know this is probaly way more information then you asked for (or needed), but there you go.
 
Keep in mind light pressures or excessive headspace will show flattened primers, and oversized fireing pin holes and weak striker springs will show cratered primers. Soft brass can yield and have ejector marks on the head. The signs are not always of excessive pressure, but do show a problem somewhere in the load that should be pin pointed.
 
ol' Joe,

Excellent points...every one of them. It usually takes a while (experience) to know exactly whats causing what and why.
 
Caseheadextractormarkscloseup.jpg


These look like WBY factory ammo. My last batch (2002 vintage) of 270 gr Hornady 378 BEE factory ammo clocked 3215 fps!!!!

Pulled the bullets and there was an average of 118.2 grain of MRP (my guess). My MRP yielded same velocity and pressures.
 
My 30-378 with Norma brass, 200 grn AB and 105 grns of Retumbo left those shiny ejector marks. 104 was good and no difference in velocity 3265. SO I backed way off to 101 grains and the load really shoots @ 3165.

CC.
 
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