Question about case seperation

Aznative

Aznative

New member
I've always checked for case seperation after three reloadings. If I feel a nick/catch starting inside the case just above the web, the case is thrown out. What I've noticed is that the streched out section that is starting to seperate is always in just one area of the case. I check the cases in three or four locations. I'm just wondering if I could get by with checking my cases every other time. I really don't believe any of these cases would seperate, but I do so out of caution. If I did shoot them one time and caught the seperation on the next go around, I believe I would be ok. Just wondering what some of you other long time reloaders do about this. BTW: I shoot a lot of semis, and I always full length resize which is harder on the brass. I do check my size die with RCBS precision mics so I'm not over compressing my brass.

What do you guys think of checking every other time, or should I stay with after every shooting.
 
Question: How many case head seperations have you had?

I shot AR's on p. dogs for two years and I never had a problem using Federal brass which is the softest of them all.

I did a visual inspection when full length sizing, and if I saw a ring (stretch mark) in front of the Web, I tossed the case. Otherwise, I never gave it another thought.
 
Case head separations are always caused by too much headspace. Don't push the shoulder back too much and the case won't stretch enough to cause separations.

It's not rocket science, use a case shoulder length gauge and only push the shoulder back .001-.002".

Jack
 
Quote:
Case head separations are always caused by too much headspace. Don't push the shoulder back too much and the case won't stretch enough to cause separations.

It's not rocket science, use a case shoulder length gauge and only push the shoulder back .001-.002".

Jack



+1

If the neck is resized, and the brass chambers in your rifle, then you are good to go.
 
All the guys are giving you good advice. Cases stretch when sized to much or you have excessive headspace.

I use Lee's Deluxe die sets for all the varmint rifles. Neck size after the first firing til the case needs full length sized again.
 
Texas tweeter: the rounds I'm talking about are mainly 223, 243, 308,3006. These are the loads that I shoot in semis. Like I've said in my original post: "I do check my size die adjustment with RCBS precision mics so I'm not over compressing my brass." I've also checked how much the brass is streching after being shot with the precision mic. THese two steps eliminate the possiblilty of too much head space and excessive resizing. I do resize about .001-.003 under max sammi case deminsions. I do full length resize after every shooting since I'm shooting ARs. I attended an M1garand clinic a long time ago, and the host said that the semis do work the brass harder than a bolt gun. That statement made sense to me since you are extracting the brass under fire/pressure. Ackleyman: I've never had a case seperation. I agree that Federal brass is the softest out there. I've always have caught them and have thrown the brass away before seperation. I check the case internally by taking a hard probe/dental tool and scratching the insides of the case at 3 or 4 point around the brass just ahead of the web. If I feel a catch, the brass gets tossed. I have some brass that has been reloaded 8-10 times. After every shooting I throw out 4-6 per hundred. Jack Roberts the RCBS precision mic is a sholder case gauge that works like a micrometer.

Here is some more info on the RCBS precisin mic:
http://www.midwayusa.com/eproductpage.exe/showproduct?saleitemid=477756&t=11082005
 
One thing I want to clarify about my initail post. I don't worry about case seperation untill the brass has been reloaded three times. After the honeymoon is over, I check for seperation everytime the brass is reloaded.
 
Quote:
What round are we talking about here, need to know what kind of pressures we are talkinga bout.



It makes no difference - pressure has nothing to do with head separations.

It is a headspace problem and comes from excessive FL sizing.


.
 
Catshooter, the way I see it. I don't have much of a choice shooting the AR platform but to push the sholder back enough to ensure proper feeding. I've always have felt and have found that with a bolt gun, you don't have to fully resize the brass as much as semis. In fact, neck sizing every other time works well as long as you don't mix brass among different rifles of the same caliber.

I would like to try and check for head seperation every other time the brass is shot? I would like to see what other semi shooters are doing out there that have brass that has been shot 5 or more times?
 
Quote:
Catshooter, the way I see it. I don't have much of a choice shooting the AR platform but to push the sholder back enough to ensure proper feeding. I've always have felt and have found that with a bolt gun, you don't have to fully resize the brass as much as semis. In fact, neck sizing every other time works well as long as you don't mix brass among different rifles of the same caliber.

I would like to try and check for head separation every other time the brass is shot? I would like to see what other semi shooters are doing out there that have brass that has been shot 5 or more times?



AZ...

I understand your your problem, but there are ways around it.

The usual culprit of feeding problems in gas guns in not the shoulder position, but the body diameter. If the body is large, then the case sticks in the chamber, long before the shoulder contacts the chamber.

If you back off the FL die a full turn, and then size a case, put a bullet in it (no powder) and try chambering it from the magazing... if it chambers, good, if not turn the die down a little and do it again, until the case just chambers with the minimum sizing.

If you are even 15 thou off the shell holder, you will not touch the shoulder, and your case stretching separations will stop.

The goal in sizing, whether for a bolt gun or a gas gun, is to size as little as possible, and have the gun feed and function reliably


.
 
JUst check the area in front of the web, and use s seal pick (or a dental probe as u use) to check the inside, and you should be ok. I was asking about the pressures involved because I have always thought that Higher pressure guns are more prone to case head seperation, when dealing with semis, lever, or pump action rifles that need to be resized. Now i dont shoot semis, just bolt and lever, but I assumed they had a weaker caming making it hard to chamber a round if you didnt bump the shoulders back a little. I may be way off course here as I mainly reload for my bolts.
 
Texas t. That is basically what I've been doing. What I want to do is see if it is safe enough to only check every other time I reload. I guess it would also make a difference how well you are performing this test.

What I'm going to do is take some of my rejected cases. I probably have a dozen or so in my loading room's trash can right now, and I'll reload them. I'll shoot them single shot so I don't have another bullet in the magazine to jam the case in even tighter if one does break. I'll use a little bushmaster with a chrome lined chamber so they won't stick as bad if they do break. I'll just shoot the gun from the hip for safety reasons and still wear shooting glasses. I'll just push the envelope untill I found out how far is too far. I knew a guy that would still use marginal cases for DCM competition. He would only use them on the slow fire positions and he had a GI stuck case remover just in case.
 
Quote:
Case head separations are always caused by too much headspace. Don't push the shoulder back too much and the case won't stretch enough to cause separations.

It's not rocket science, use a case shoulder length gauge and only push the shoulder back .001-.002".




Bingo! Right on the money. Here's my tail of woe if you want to read it.

The gun is an 03 Springfield I bought at a NYC pawn shop about 50 years ago for $30 bucks.
Put at least 30,000 handloads through it over the years. In fact I could drop a bullet into the chamber and it would rattle out the muzzle. Ha.

Rebarreled it 6 months ago with a heavy Adams and Bennet 26” barrel. I gave it to my favorite gunsmith (no longer my favorite) who cut the chamber, receiver threads and extractor slot. It was mounted into a benchrest flat base stock that I modified and manufactured myself.

Bought all new 30-06 brass and started with light to moderate loads. The accuracy seemed to be acceptable until the barrel got hot. By the time I to reloading the cases the third time, I noticed the ring around the base above the web. The cases were neck sized only. I used the RCBS case master tool and went through every test in the book. They were failing the possible head separation exam. Some, the little sharp point would grab into the crack.

I took some cases, put water into a small glass, put the cases with the primers not removed base first into the glass and blew into the case. A fine stream of bubbles came out of the area. So went to my “gunsmith”
And he checked the head space with me watching and it passed go and no-go. He said it was my loads.

Then I bought an RCBS case comparator and a set of head space gauges. Found that the cases had stretched at between .008 and .010 with a number of cases almost .015. These case had a very visible cracks

When I checked the chamber with the gauges I found that the bolt closed on the no-go gauge with no resistance but almost closed on a FIELD gauge. Additional research turned up this:
The “gunsmith” used an old military reamer which he got surplus about 30 years ago. His head space gauges were old military and NOT SAAMI spec.

The chamber was made military oversize so the rounds would work through a dirty weapon in the field.
The chamber cut near the base was not cut round but was somewhat ovate in shape as measured by my new competent gunsmith

When I confronted him with this he said he got no complaints from anyone else. I said “this is the only barrel you chambered for 30-06 in your life” and walked away.

To correct the problem my new gunsmith cut off 3/8” off the end, re-reamed the chamber using the correct reamer and precision lathe. The job was finished over a week end. Now works and shoots magnificently.

Another trick I did was to use an old feeler gauge and take the .001" feeler and cut into small round disks the size of the case base. Put them 1 at a time behind the go gauge until the bolt would not close with light pressure. It turns out the true headspace is .003". The SAAMI no-go spec is .004"

Case stretch- the most I measure now is from 0 for very light loads to .003” for heavy loads with no cracks or bulging of the sides above the web.

I had to discard 76 out of 100 new cases because of gross incompetence.

If you were to measure new unfired cases using a shoulder length gauge you would find some as much as -.003 shorter and some +.003 longer than SAAMI specs. The bolt will close on all of them. Some case may need to be fired 3 or more times before they stretch to conform to individual chambers. Maximum accuracy may not occur until that happens.

That's my tale of woe but I learned fast..



Frankie B.
 
Quote:
"...
Another trick I did was to use an old feeler gauge and take the .001" feeler and cut into small round disks the size of the case base. Put them 1 at a time behind the go gauge until the bolt would not close with light pressure. It turns out the true headspace is .003". The SAAMI no-go spec is .004"

Frankie B.



I use Scotch tape to test for working headspace. It is 0.002" (2 thou) thick.

I build layers on the casehead and trim the edges so there is no overlap - when the bolt shows the beginning of resistance (firing pin out), then I count the layers and multiply x 2 and that is the real working headspace.

.
 
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