Inspecting Your Brass — What Case Flaws Reveal
Ever wondered what caused a particular bulge or marking on a case? And more importantly, does the issue make the case unsafe for further use? Sierra Bullets Ballistic Technician Duane Siercks offers some insight into various issues and their causes in this article from the Sierra Blog.
Incipient Case-Head Separation
This is a Winchester .308 Win case that has a real issue. This case has a very obvious incipient case head separation in the process of becoming a complete failure.
This is most commonly caused by over-sizing the case causing there to be excess headspace on the case. After a few firings and subsequent re-sizing, this case is just about ready to come completely apart. Proper die adjustment is certainly a requirement here. Of course this case is not safe to reuse.
Excessive Pressure (Load Too Hot)
If you will notice in the picture of the case rim, there are two pressure signs to notice. First, look at the primer. It is basically flattened to about the max of what could be considered safe. If this was the only pressure sign noted, I would probably be fine with this load, but would constantly keep an eye on it especially if I was going to use this load in warmer temperatures. This load could easily cross into the “excess pressure” realm very quickly.
There is another sign of pressure that we cannot ignore. If you’ll notice, there is an ejector mark apparent that is located over the “R” of the R-P headstamp. This absolutely tells us that this load would not have been in the safe pressure range. If there were any of these rounds loaded, they should not be fired and should be dis-assembled. This case should not be reloaded.
Split Case-Neck
Here we have an R-P .22-250 case that has died the death. Everything looks fine with this case except the neck is split. This case must be tossed.
A split neck is a normal occurrence that you must watch for. It is caused by work-hardening of the brass. Brass cases get harder with age and use. Brand new cases that are stored for a period of time can become hard enough that they will split like this case within one to two firings. I have had new factory loads do the same thing. Then as we resize and fire these cases repeatedly, they tend to get harder and harder. Eventually they will split. The life of the case can be extended by careful annealing practices. This is an issue that would need to be addressed in an article by itself. Of course this case is no longer usable.
In the classes that I teach, I try to use examples like this to let the students see what they should be looking for. As always, if we can assist you, whether you are new to reloading or very experienced, contact us here at Sierra Bullets by phone at 1-800-223-8799 or by email at sierra@sierrabullets.com.
Dented Case Body
Here we have a Lake City 7.62×51 (.308 Win.) case with two heavy marks/dents in the case body.
This one may be a bit of a mystery. It appears as if this case may have been caught in the action of a semi-auto rifle when the firearm jammed or the case failed to clear during the cycling process. I probably would not reload this case just to prevent any feeding problems. This also appeared to be a factory loaded round and I don’t really see any pressure issues or damage to the case.
CLICK HERE for MORE .223 Rem Case Examples in Sierra Blog
It is very important to observe and inspect your cases before each reloading. After awhile it becomes second nature to notice the little things. Never get complacent as you become more familiar with the reloading process. If ever in doubt, call Sierra’s Techs at 1-800-223-8799.
Similar Posts:
- Case Diagnostics — Find the Flaws in Your Cases
- How to Detect Flaws in Cartridge Brass — Case Diagnostics
- Case Diagnostics — How to Find Flaws in Cartridge Brass
- Case Diagnostics — How to Find Defects in Cartridge Brass
- Eyeball Your Brass — How to Diagnose Flawed Cases
Tags: Cartridge Brass, Case Separation, Duane Siercks, Flattened Primer, Pressure Signs, Sierra Bullets, Split Neck
This is very useful information, and worth repeating every so often as a reminder.
The dented case in the last image is caused by the case ejecting out of an AR and hitting the brass deflector. Stick one of those small felt pads on it and it will no longer dent your brass. I had the same issue and did this simple fix.
Excellent article. Thank you!
I am recently experiencing a discoloratin at the base of my 6.5 cases. I am shooting 142 gram Sierra Match bullets with a load of 40.5 H4350.
This is out of my RPR.
Anyone have any ideas?
I can send you photos.
Thanks
my ar shoots and ejects fine but the brass case mouth is perfect 1/4 flat dent on case mouth how can i fix it. thanks jerry ps 20 in.6.5 grendel all ammo.