C308 and Lake City brass

[Hogpost]

Love my C308; over 1200 rounds thru it without a hitch, very accurate, amazingly little recoil, and easy to reload for. I use 150 Gr boat-tail spitzers over 40 Grns 3031, COAL 2.800; full-power military duplicate, but not a max load by any means. Use both German aluminum and Spanish steel CETME magazines interchangeably.

Been using once-fired NATO brass, mostly Taiwanese & South Korean, some German. Some I have even re-reloaded (ie, fired the third time) with no problems. For the first time, I ran 50 rounds of once-fired Lake City 2016 NATO brass, with scary results: About round #40, the shoulder & neck of one case broke off & stuck in the chamber, so the next round jammed in it. I checked all my fired brass and noted most showed a stress line in the same area, and a dozen had actual cracks. See the attached pic.

Everybody tells me how wonderful genuine LC brass made in US-of-A is. Don’t bet your life on it; from now on, I’m sticking with the good foreign stuff. How embarrassing!

Anybody have similar experience?
209762

[Larry Gibson]

What dies did you use to size the LC cases?

[Hogpost]

I used the same Lee dies I used on the preceding 1100 -or-so cases.

[gnostic]

I had an HK91 that shot great with LC cases, I never attempted to reload them. They just looked like a train wreck looking for a place to happen...

[BUCKEYE BANDIT]

Watching with interest.Just purchased some newer L.C. 16 to add to stash.

[Hogpost]

Yeah, Gnostic, I've only re-reloaded a few that came from my gun, just to see. They worked fine, but I don't plan to make a habit of it: takes too much time to find the ejected brass, then sort through them to remove bent-in case mouths, and I'd still have questionable brass.

[Larry Gibson]

You might want to read my post #21 in http://castboolits.gunloads.com/showthread.php?349672-My-M1A.

I have also reloaded for a couple CETME rifles and several HKs with the fluted chamber. Any Milsurp LC M80 cases purchased surplus you find these days will 99.9999999999% of the time have been fired out of M60s or more probably M240s. That is very hard on the cases to begin with. Sizing in standard dies just pushes/flows the brass forward during sizing which is why the necks appear long on your cases. The brass to make the neck longer comes from the body (side) of the cases. That is why you got incipient case separation. The X-Die, properly used, prevents that.

[BUCKEYE BANDIT]

Some of the best advise once again.

https://www.midsouthshooterssupply.com/item/0004437812/308-winchester-full-length-x-die-set

I believe it was when I was reading Bruce B.'s work that I first became aware of them.Just the extended brass life more than pays for them.And doesn't even add another operation once set up. THANKS LARRY !!!!
You might want to read my post #21 in http://castboolits.gunloads.com/showthread.php?349672-My-M1A.

I have also reloaded for a couple CETME rifles and several HKs with the fluted chamber. Any Milsurp LC M80 cases purchased surplus you find these days will 99.9999999999% of the time have been fired out of M60s or more probably M240s. That is very hard on the cases to begin with. Sizing in standard dies just pushes/flows the brass forward during sizing which is why the necks appear long on your cases. The brass to make the neck longer comes from the body (side) of the cases. That is why you got incipient case separation. The X-Die, properly used, prevents that.

[WILCO]

For my needs, LC brass is just fine. I'll keep buying it.

[exile]

To begin, let me apologize in advance for the thread hijack, but I cannot resist asking, Is the example given of case damage also present with once-fired Lake City .556 brass? If so, why or why not? Thank you in advance for your responses.

And let me take this opportunity to wish everyone on Cast Boolits a Merry Christmas!

exile

[308Jeff]

This is interesting. Why the separation at the shoulder? We usually expect to see it at the case head.

Do you have any brass that you haven't resized yet? Would love to know how far beyond SAAMI they've been pushed forward.

[Larry Gibson]

To begin, let me apologize in advance for the thread hijack, but I cannot resist asking, Is the example given of case damage also present with once-fired Lake City .556 brass? If so, why or why not? Thank you in advance for your responses.

And let me take this opportunity to wish everyone on Cast Boolits a Merry Christmas!

exile

It very well can be, especially if the cases were fired in M249s. However, I do use a standard .223 X-die to reload all my 223/5.56 for all my gas guns.

[Hogpost]

I understand, and greatly appreciate, all the responses and detailed information. I will likely plump for an X-die just for the extra margin of safety. And I'll see if I have some of that LC brass left unsized.

However, please note that I use this once-fired brass only once, not 3-5 times; and on some 1100 cases over the past year, I've had this condition only on LC 2016 brass. No S. Korean brass, no German brass, no Taiwan brass has shown anything remotely like it.

And as 308Jeff points out, the separation is at an unexpected place. I was wondering if someone else had encountered this same situation.

[vzerone]

Hogpost, just think about it. Thousands upon thousands of reloader have been using other dies besides the X dies and not having problems. The X is a fairly new die that didn't exist so many years ago. Something else is going on with you incident. The fact that it didn't happen with the other foreign brass proves that out.

[popper]

Lee die problem? Thicker case? If the expander is too large it will pull from the shoulder area. I use RCBS but decap & expand with M die. No problem in many LC07 stuff that HAS been fired in MG. The X die supposedly has a different expander and doesn't pull from the shoulder area.
Looking at the pic, it's something else. Neck has the flutes but body doesn't have much. I suspect neck is stuck but body isn't - so body moves. If you notice factory loaded, annealed completely over the shoulder area. Not familiar with the C308, isn't it one with the roller lock?

[308Jeff]

I'm purely speculating, but I doubt it's related to 2016 LC brass, but rather to what that 2016 LC brass was fired in (and just how badly it deformed the brass).

Although I have doubts that a military armorer would allow something that far out of spec to be operated, we can certainly find out by inspecting that unsized brass and see just how far out of whack it is. If it's not anything crazy, then I guess we can go ahead and lay the blame on the headstamp/batch.

[KenT7021]

The brass may have been run thru a minigun instead of an M60 or M240.I tried resizing some brass from a Cobra gunnery range once and wound up scrapping the brass.I was picking up brass from a Cobra test firing of a gun that was malfunctioning and noticed the primers were missing on some of the cases and the primer pocket was .30 diameter.I had the bird brought back in and pulled the gun.One barrel had a separated case in the chamber and the gun was actually able to chamber and fire a round in that chamber.The gun was not damaged.The pressure must have been rather high.

[Larry Gibson]

Hogpost

I suspect the "mostly Taiwanese & South Korean, some German" cases you've not had incipient case separation problems with (yet) were all originally fired in your C308 and were not fired in MGs(?). That would account for the 3 times fired so far w/o problems. The difference is the once fired LC cases you bought were fired in a MG of one kind or another. That is the difference. You X-die will get you numerous firings from the LC cases. Perhaps not as many as I got in the test as mine were not fired in a MG the first time. It will also extend the case life of your other brass though since some has been fired 3 times and reloaded with the Lee die you may experience incipient case separation sooner.....remains to be seen but my guess is the case rims and bodies will be "chewed" up before that occurs. That was my experience with the HKs having fluted chambers.

Jeff and Ken are correct. Obviously someone doesn't realize the chamber dimensions for milsurp machine guns (specifically the diameter of the chamber) is larger than commercial spec. Obviously they also don't have any idea of the residual pressures during FA fire and that the expanded case doesn't contract as in other firearms. That's why such fired case most often won't even rechamber (NS'd w/o FL sizing) in the same weapon they were fired in. Since militaries don't reload for such service weapons they don't care if the brass is damaged.

The over size expansion is in the case body. When sized in a standard FL die the sides of the case are pushed in. The brass sides do not compress back to their original thickness as w/o resistance the brass flow forward. That pushes the shoulder forward which then must be set back for proper headspace. The brass continues to flow forward into the neck which elongates the neck. The case is now thinner at some portion of it's length. Most often the thinning occurs at or just in front of the expansion ring ahead of the case web. However, as we see in this instance it can happen anywhere along the case body. Where generally depends on where the greatest expansion of the case occurred when fired and how much sizing back down the FL die does.

What the X-die does is stop the forward flow of the brass during sizing so the case wall does not get thinner. Yes thousands of reloaders have gotten 3 -5, sometimes a couple more firings depending on the load, out of SA rifles. However, they did not do that with service M80 level loads using MG fired cases. The X-Dies have been around for many years and have been a god send to extended case life, particularly in SA rifles. Not having to trim cases is also a boon.

[edslau33]

So I am going to add a little context here. I have never reloaded lake city. I have bought some for my c308 and it hated them. So bad that my local gunsmith decided that my chamber must be out of spec. Would extract from chamber and try and put same case back in. Broke two extractors. I sent back they replaced trigger group. Sounds odd. Sent it back and have not had time to fire it. They may not like lake city as a whole.


Sent from my iPhone using Tapatalk

[vzerone]

My experience is I've been using RCBS standard steel resizing die, Hornady bushing neck sizing dies with the capability to bump the shoulder back, and a Lyman standard neck sizing only die. I also use the Lyman neck sizer to size my 30-06 cases. These are shot from M1 Garand (30-06 of course in my instance) M1A National Match, various AR 10's with 7.62 Nato chambers. Yes I've been shooting those SA's with just neck sizing and have not had one issue with them as far as feeding, fitting the chambers, extraction, or brass failure. Some cases I lose with severe mouth damage due to bad denting. This never happens in the AR10's. My opinion the AR10 is very forgiving on brass, more so then the M1A's and Garands. I use strictly military cases. I have on occassions used commercial in the 30-06. I have a bunch of Canadian 7.62 NATO cases and they are really excellent. The rest are all LC of various vintage as far back as the 60's. BTW I have a set of X dies but rarely use them as I have no need for them. I also own and shoot a Russian SVT 40 and it also has the distinction of having a fluted chamber. I shoot both cast and jacketed loads through it. I am currently using a set of LEE dies for it, but also neck size only for it too, and have no brass problems with it other then chewed up case mouths because of it's violent extraction. The cases for this are Graf's.

Many people try to get others to do what they do. Maybe I'm guilty of that a little. I'm giving my honest opinion on this matter. All I can say is go ahead and buy a set of X dies and make your own opinion. They definitely do keep the case from growing and having to trim. The patent for the X die was filed March 13, 1996. That's when it was file and not when the dies were in actual use. One more honest statement is I don't shoot a steady diet of factory equivalent jacketed loads. After all this is a cast bullet forum right? I do, however, shoot a lot of cast loads that are in the range of jacketed factory loads.

I'm holding firmly the OP has something other then a resizing die issue going on. It does appear, as others have mentioned, a brass issue with the LC. What his gunsmith thinks the trigger group has to do with his brass problem is beyond me, other then if he feels the firing pin strike is forcing the case deeper in the chamber thus causing a headspace problem, but then why change the whole group rather then say just the spring.

[308Jeff]

Because I have somewhere around 12K (maybe more?) pieces of LC brass, this post has really been on my mind.

I've been gradually going through all of it, processing about 1,000 at a time. There are a few hundred pieces that I have fired once, making them twice fired, that I have reprocessed.

What I'm really interested to find out is what the dimensions of your unprocessed LC16 are. Would really like to figure out if it's that particular year that has issues, if it's due to being grossly overstressed due to crazy headspacing, or if there's really an issue with LC brass. As this is the first time I've ever heard of a LC brass failing on just a second firing, I'm inclined to believe it's either related to a bad batch, or you got some that was severely abused on its first firing.

Do you have any left that you can measure?

[popper]

3033 bullet? Would really be interesting to see a pic of the unprocessed next to a fires & processed cases. Could be the MG fired has a different shoulder area? I've only gotten radial neck cracks from half jacketed in the 30/30. I run 100 (MGd) LC at a time, reload probably 5-6 times and then scrap if I see problems.

[Hogpost]

OK, guys, I rounded up brass and measured it, as below. But first, I want to make sure everyone understands where I’m coming from:
1. All brass was purchased in a single lot of once-fired NATO brass from a single US military auction. I have no reason to believe the different “brands” were handled any differently by the Guys in Green on the range. I would easily believe it was ALL fired in machine guns.

2. I have ZERO interest in multiple reloading of this brass: once my C308 chews it up and throws it ten yards into the brush, it’s not worth even looking for. I re-reloaded 100 rounds of Taiwan brass only (fired only 50, no problems) just to see what my safety margin is, nothing else.

3. My concern when first posting this problem is that the LC brass seems to fail the first time I use it; none of the other brass shows the problem.

SOoo...I have sorted out and measured four lots (all I have left in sufficient quantity to compare), as follows:

A. 50 Lake City as-received once-fired
B. 50 Lake City reloaded once, still unfired
C. 50 Taiwan (TAA07 headstamp) as-received once-fired
D. 50 Taiwan (TAA07) reloaded once, fired, reloaded second time, still unfired

Overall length:
A. 26 @ 2.007-2.015; 15 @ 2.015-2.020; 9 @ 2.020-2.023
B. All 2.0019-2.023
C. All 2.006-2.013
D. All 2.007-2.015

Diameter at the shoulder:
A, B, C, & D: All .452-.456

Diameter at the base: A, B, C, & D: All .468-.469

Straightness of sides, noted by rolling on a granite surface plate illuminated from behind: no bulge either ring-shaped nor “guppy belly” on any case.

Conclusion: this lot of Lake City brass is softer or weaker or….:
assuming it was in length spec when originally fired by the military, it stretched to out-of-spec on the first firing, whereas the Taiwan brass did not; and the Taiwan brass was still within length spec after TWO reloadings on the same tooling.

Secondary conclusion: none of this brass seems to have been fired in wildly oversized chambers or in weapons which brutalize the brass. Certainly none of it was fired in fluted chambers; if it was used in machine guns, these choppers were pretty gentle.

[308Jeff]

Thank you for the follow up, Hogpost.

I could be completely wrong about this, but because your separations are occurring at the shoulder, that's the area that I'm speculating is the suspect. We have OAL measurements, but not base to shoulder. I think we're only seeing part of the picture?

Do you have a Hornady headspace tool or an RCBS Precision mic? Would be very interesting to see a comparison of how far the shoulder has been pushed forward on the various brass.

In my mind, I'm speculating that there are two possible scenarios:

1) There's something wrong with the LC Brass
2) The LC brass was fired in something with unusually generous headspace allowing the shoulder to be pushed VERY far forward. Maybe more than 10, or even up to 15 thousandths or more?

I dunno.

[vzerone]

Just like I said many posts ago, you had/have something else going on besides what type of reloading die you use and now we see that it's more then likely a bad batch of LC brass. This is something that no die including an X Die will fix. Now maybe if you had new or better shape brass and started with the X Die it would keep it from growing, but as you mentioned you have no intentions of firing the same brass over and over. So in that respect don't waste your hard earned money on another set of dies you don't need.

I'm trying to think of where I saw a rubber bumper that you afix to your rifle and it keeps the cases from getting mangled up. I want to say on my good friends Valmet. It use to nearly bend the case in half and toss it far. Well the rubber bumper worked, but then it tossed his brass ever further like one or two counties away. If he found it, it was in better shape. Not familiar with if they have something like that for the C308.

[gnostic]

Yeah, Gnostic, I've only re-reloaded a few that came from my gun, just to see. They worked fine, but I don't plan to make a habit of it: takes too much time to find the ejected brass, then sort through them to remove bent-in case mouths, and I'd still have questionable brass.

No kidding, the lines impressed on the brass scared me off... Also, my rifle seemed over-gassed, it bent the rim during extraction...

[Larry Gibson]

Overall length:
A. 26 @ 2.007-2.015; 15 @ 2.015-2.020; 9 @ 2.020-2.023

There's the problem cases........I too would like to see the headspace measurement of those cases. You might size one and then cut it lengthwise to see where the thinning is taking place. Personally I would pitch those cases.

[Motor]

I've never had any issues with LC 7.62x51 brass of any year. Personally I'd chuck that one up to simply a fluke.

Graf&Sons just had an awesome sale. Blemished, PRIMED LC 7.62x51 for $15.99 per hundred. These are NEVER BEEN FIRED casings. Even if you didn't use the primers (why wouldn't you) this was an awesome chance to get some very good brass.

Motor

[vzerone]

I've had a bunch of those never fired LC cases. They were primed too and mine weren't blemished. Got them from Wideners a long time ago. Fine brass!