Head Seperation/Gun Type/Paper Clip Test

[Brian Pfleuger]

I have Hornady cases in 204 that were fired in factory loads and then reused with just Lee collet neck sizing. I have both 204 and 7mm-08 Norma cases that were fireformed with Trail Boss and then neck sized in the Lee collet die. The 204 are all fired in my M77 MkII rifle while the 7mm-08 have all been fired in my Encore.

For you paper clip test head separation ring guys...

I am not able to detect any sort of ring whatsoever in any of these cases. Is it that difficult to feel or is it likely that there aren't any? Some of the 7mm cases have been fired 4 or 5 times with full power (58k psi range) loads.

[GP100man]

No ,it`s a very simple & direct test, just stik it in all the way then scratch the side of the case .

Bend ya paper clip into a L , if you ever find 1 you`ll know it rite off !!

If ya see someone shootin the Handy Rifles pick up a peice of there brass & check it , some of those little rifles have BOKOO headspace & will stretch a case in 1 firing .

Also if ya have to trimm alot after each firin is a sign of excess headspace !!

[Sevens]

If all your cases are neck-only sized with the Lee collet sizer... I don't see why you'd see a case head separation. That part of the brass isn't being flexed.

You fireformed it, it got stretched just a touch. Then it was never set back (by a FL sizer) so it never had to jump forward again during firing.

You'll likely split some necks soon... or maybe not! I don't see why you should expect a case head separation.

That's just one more great reason to use the Lee collet neck-only sizer. (it's a great tool!)

[Brian Pfleuger]

Originally Posted by GP100man

No ,it`s a very simple & direct test, just stik it in all the way then scratch the side of the case .

Bend ya paper clip into a L , if you ever find 1 you`ll know it rite off

Yep... that's what I'm doing... haven't felt a thing yet.

Originally Posted by Sevens

If all your cases are neck-only sized with the Lee collet sizer... I don't see why you'd see a case head separation. That part of the brass isn't being flexed.

Hm. Ok, that's in line with my thinking. That's why I fireformed the cases with Trail Boss first. The pressure was kept below the point that the brass sticks to the chamber so, in theory, the case should have slid back to the breech and the shoulder would have pushed forward... no stretch at all.

It's just that I keep reading about head separation and guys throwing away brass (by default) after as few as 2 loadings and I'm thinking "Am I missing something? Maybe I'm going to blow myself up?"

The split neck thing is possible. I have begun to feel a definite difference in the way some of the cases feel when I size them. I assume that some annealing is in order, but I'm not at all convinced that it can be done safely, reliably, effectively and, especially, without being a great big pain in the backside, by most home reloaders.

[Sevens]

Well, I'm admittedly a guy who has never done annealing... but from what I've read and seen, I don't think it's a big operation and I'm sure that even a turkey like me could pull it off.

Blow torch, shallow baking pan with water and the proper technique, I don't think it would be all that tough.

Is your brass growing, are you trimming? As the brass flows, it comes from somewhere and you trim it off. Eventually, it's going to thin somewhere. I'm guessing it'll be the case mouths.

[Brian Pfleuger]

Originally Posted by Sevens

Is your brass growing, are you trimming? As the brass flows, it comes from somewhere and you trim it off. Eventually, it's going to thin somewhere. I'm guessing it'll be the case mouths.

Rarely, I find one in need of trimming. It's a little odd to me. Sometimes the cases seem to shrink a little, every so often one needs trimming, mostly, they stay the same. The last batch I processed... about 36 cases, had 3 that were trimmed by the Lee tool.

Mostly, they just stay the same. 2.025 inches +- a couple thou.


I don't think I'm getting the neck tension I used to though. I'm pretty sure the necks are hardening up somewhat on the cases that have been repeatedly sized.

I have pretty thoroughly researched quite a number of "home brew" annealing techniques. I'm convinced that they are all either ineffective, too much of a pain in the butt, too difficult to be done consistently enough to be safe, or just completely unsafe.

[Gbro]

I have neck sized some of my loads for 30 years. I do not push the velocity for the most part and loads like my .270Win ,that used to show sign's of head separation after 3-4 reloads now never show any signs.
I did have a whole batch of brass start separating and had 6 without any indication of separation fully separate in my .257Rob'ts because I had been neck sizing for years and then returned to full length sizing with the same brass. The old brass that was doing its job so well was to hard and it had to go in the scrap bin after being hammered flat so they couldn't be used again.

[alloy]

I use a bent tip pick thats alot stiffer than a paper clip but when it starts to get that groove in there, you will recognize it.
Bout 1/8-1/4" up from the bottom inside.

[HiBC]

FWIW,a while back I referenced an article in Handloader mag about developing an accurate .308 load.The author used about every brand of quality brass.He loaded them till they head separated.Norma brass had far superior case life,about twice tbe loadings of the brand that came in best for accuracy.

[FrankenMauser]

FWIW,a while back I referenced an article in Handloader mag about developing an accurate .308 load.The author used about every brand of quality brass.He loaded them till they head separated.Norma brass had far superior case life,about twice tbe loadings of the brand that came in best for accuracy.

I know the article you are referring to. It is bookmarked, and the issue is on one of my book shelves.

If anyone is interested in an informative read (though arguably dull), it was the December 2008 issue of Handloader. The article is titled, "Developing an Accurate .308 Load" (or, more appropriately, "Developing the Most Accurate .308 Winchester Load" {cover title}).

Accuracy was determined by averaging 5-shot groups on 4 targets (four separate 5-shot groups).
Case life was determined by full length sizing and firing a case from each type of brass until case head separation.

Best accuracy came from Nosler brass (0.3281" average group).
Worst case life came from Nosler brass (failed on 10th reload).

Third worst accuracy came from Norma brass (0.5469" average group).
Best case life came from Norma brass (failed on 23rd reload).

Middle-of-the-road accuracy came from Remington cases (0.4375" plain, 0.5313" plated).
Second and Third best case life came from Remington cases (failed on: 19th reload - plain, 21st reload - plated).

-----
You should be able to feel the groove, when a case starts to stretch.
As pointed out in the article referenced above... Once they start to stretch, they go fast. The case walls can thin by as much as 0.008" in a single firing. The FC military brass tested in the article showed 0.008" of thinning on the 9th reload (first detectable sign), and suffered total case head separation on the very next firing (10th reload).

[Brian Pfleuger]

Originally Posted by FrankenMauser

Accuracy was determined by averaging 5-shot groups on 4 targets (four separate 5-shot groups).
Case life was determined by full length sizing and firing a case from each type of brass until case head separation.

Third worst accuracy came from Norma brass (0.5469" average group).
Best case life came from Norma brass (failed on 23rd reload).

Holy Smokes! If that holds true, these things should last FOREVER. If they go 23 reloads with full resizing, imagine what they'll do with just neck sizing!?

Accuracy at that level is meaningless to me. Less than 1/4" difference from "best" is well beyond not just my capability but also anything that I'll ever need anyway.

I'm surprised that I haven't had to size the bodies on any of these cases yet. I had concluded from reading that the cases were likely to need to be resized after a couple or 3 firings because they would begin to get to tight in the chamber. So far, they all fit and extract just fine even after 4 or 5 times.

[Ike666]

I was continuing with my testing of .308 loads this past weekend and had 4 LC Match cases show the dreaded bright ring indicating an incipient case head failure.

With the paperclip test a noticeable dip could be felt in all four.

All these cases had been full length sized with a Dillon Carbide sizer.

By comparison, a batch of loads with the same brass that had been fireformed to the chamber and neck-sized with the Lee collet then loaded to the same specs did not show any pressure signs. The primers were slightly flattened but still had some round at the edges, but more importantly none evidenced any dip at the critical ring point.

(Yes, I need to reset my Dillon sizer).

I had to feel a positive dip with the paper clip before I trusted what I was feeling. Its kind of hard to master the technique with a negative indication.

@HiBC BTW, I ordered that copy of Handloader after your suggestion. It is a wealth of information. It took the guy a whole shooting season to run the tests.

[HiBC]

Ike666,Good for you!Happy to help.