First case of incipient head separation UPDATE: 2nd case found
- Thread starter Onagoth
- Start date
Not really. The .308 operates at 51,000CUP and the .300WM is at 52,000CUP. If the difference there is enough to cut case life in HALF, I would suggest knocking your load down 0.5 gr...
Missed this one.
Pretty sure the 300WM operates at 62,000 and the 308 at 52,000.
- Location
- The Conservative part of Ontario
Brass flows forward in the cycle of firing and reloading, that's why we have to trim at times. That brass comes from somewhere, hence even in a properly headspaced rifle, a separation can happen, but it takes along time and usually is higher on the case, if you use reasonable loads.
Headspace can be countered with neck sizing, but, as suggested eventually you need to size the case. How long that takes, depends on the loads.
If you really don't want to properly headspace the rifle, you can play with partial resizing, or try some of the fancy body dies available.
All fidly stuff of course, and not perfect.
Handgun brass for me lasts pretty much forever. I've only see separations on thin walled 44-40 brass, in a rifle with bad headspace, and heavy loads used.
The 44-40 which headspaces on the rim, has a neck of sorts, and you can neck size it to headspace on the shoulder. Worked well in the old rifle I was using at the time, seemed to improve accuracy too.
As I've never seen it on 44 Magnum brass, I'm tempted to agree that this was just a bad case.
Headspace can be countered with neck sizing, but, as suggested eventually you need to size the case. How long that takes, depends on the loads.
If you really don't want to properly headspace the rifle, you can play with partial resizing, or try some of the fancy body dies available.
All fidly stuff of course, and not perfect.
Handgun brass for me lasts pretty much forever. I've only see separations on thin walled 44-40 brass, in a rifle with bad headspace, and heavy loads used.
The 44-40 which headspaces on the rim, has a neck of sorts, and you can neck size it to headspace on the shoulder. Worked well in the old rifle I was using at the time, seemed to improve accuracy too.
As I've never seen it on 44 Magnum brass, I'm tempted to agree that this was just a bad case.
Just to add straight walled cases such as the .45acp actually shorten with sucessive resizing. There is no need for triming .45acp brass. While .40cal operates at significantly higher pressure than the .45acp these cases will shorten over the length of the life of the case as well. In the latters case I usually incur case splitting long before I have to worry about to short of case.
While I attribute my one incident of head separation in a .40 cal case likely just to a bad case what is interesting is it had all the hallmarks of head separation. The ring split occured about 1/2" above the base of the case very similar to a rifle case separation.
Take Care
Bob
While I attribute my one incident of head separation in a .40 cal case likely just to a bad case what is interesting is it had all the hallmarks of head separation. The ring split occured about 1/2" above the base of the case very similar to a rifle case separation.
Take Care
Bob
If you are asking me the caes were once fired Win out of a Glock, resizied with a Lee Sizing die down past the bulge and shot from a Tanfoglio Model "L". Load was 2.8 gr of Titegroup making 130 PF. Pretty light.
Take Care
Bob
Well, I tripped across another case which has me thinking it might be more than just a defective case. This one was a winchester case, the separation wasn't as apparent as it was in the first case, but it was still there.
So, what else could be causing this? In both cases, the separation seems to be occuring where the taper begins.
So, what else could be causing this?
In both cases, the separation seems to be occuring where the taper begins.
I don't want to contradict you just for the sake of it, but could it be the anxiety about incipient head separation is getting to you?
I ask 'cause the same thing happened to me some months back, I started worrying about it way too much and started seeing signs of it on some 10mm brass, signs that, after much consideration and research, were simply slight marks left by the place where the ramp meets the chamber.
I asked you this on the previous page but I'm not sure you answered: Did you run a sharpened paper-clip tip along the inside to see if you can feel anything? Head separation always starts from the inside...
I ask 'cause the same thing happened to me some months back, I started worrying about it way too much and started seeing signs of it on some 10mm brass, signs that, after much consideration and research, were simply slight marks left by the place where the ramp meets the chamber.
I asked you this on the previous page but I'm not sure you answered: Did you run a sharpened paper-clip tip along the inside to see if you can feel anything? Head separation always starts from the inside...
Well, I dont think I am the nervous type, its not that I am seeing the separation, the cases are actually ridging near the base and the feel is very distinct.
I wasn't sure what you meant by the paper clip thing you posted earlier, but I just checked and didn't feel anything from the inside.
even more nowSo it's not incipient case head separation per se (which makes sense 'cause it doesn't happen in pistol cases).
The ridge appears on the entire circumference of the case, not just to one side?
Could it be you need a change of recoil springs? I got a few "ramp bites" on some 10mm cases until I put in some new, stiffer springs and now the problem's gone.
Just throwin' ideas out there...
The ridge appears on the entire circumference of the case, not just to one side?
Could it be you need a change of recoil springs? I got a few "ramp bites" on some 10mm cases until I put in some new, stiffer springs and now the problem's gone.
Just throwin' ideas out there...
Well, the ridge is definitely more prevalent on one side of the case, and very mild on the other. I should mentioned that although I posted these two comments fairly close together, I have actually loaded a bunch of rounds before this issue popped up again (approx 500)
- Location
- The Conservative part of Ontario
What were these fired in?
Just wondering if it's the cut of the chamber that is the issue here.
Just wondering if it's the cut of the chamber that is the issue here.
The only thing I can think of is a weak recoil spring, which would cause your case to get out of battery too soon and the exposed base to bulge outside the chamber, pressing against the opening of the chamber and causing a ridge, which would be more noticeable on the one side (the bottom).
That, coupled with a hot load, and maybe a too sharp chamber edge, would do it.
But yeah, the fact that this only happened on a couple cases out of several hundreds is WTF-inducing.
That, coupled with a hot load, and maybe a too sharp chamber edge, would do it.
But yeah, the fact that this only happened on a couple cases out of several hundreds is WTF-inducing.
Well, I'm not overly concerned, I worked up my loads in 0.1 grain increments to 4.5 grains W231 (124 CMJ) , which isn't really a hot load I don't think.
Just keep moving on I guess, I will try swapping out the recoil spring, I have a spare factory one in my parts bag.
Onagoth I agree with H4831 I think you might just be seeing the ring left by the sizing die. My one case of head separation was a distinct split completely around the case after the 2nd firing. I have chalked it up to a bad case since I have shot a couple of thousand rds using the same load and tyoe of case with no indication of head separation after several firings.
Take Care
Bob
Take Care
Bob
