5.56 LC head stamp variations

ghbucky

New member
I'm attaching a pic of some headstamps.

These all came out of the same box of Federal American Eagle 5.56 55gr FMJ

I'm a bit surprised to see the LC headstamp, but my real question here is about the variety of the headstamps.

What I see is the + in circle indicating that is NATO 5.56, the LC stamp and 19, which I'm assuming means 2019.

But there are also some variations in small and large circles on them. I don't understand what those indicate. And are they 'matched' headstamps if they are mixed like that?

[edit] this is the ammo
 

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Multiple machines producing cases. Multiple die sets involved. Weigh some emty cases and you will be suprised.
 
But there are also some variations in small and large circles on them. I don't understand what those indicate. And are they 'matched' headstamps if they are mixed like that?

The dots indicate when and where they were produced I believe .

Interesting , I use almost exclusively LC cases in both 308 & 5.56 . I've never looked that closely at the dots on the cases . I know with the LC 308 cases with out dots are much better in quality . Cases with no dots are much more consistent in case volume as well as being able to handle higher max charges better with out sticky bolts and stretched out primer pockets .

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I've heard that the cases with dots indicate they are made on high speed machines . Don't know how accurate that is but the 308 cases with dots appear to be just a tad softer then the ones without dots . Cases with dots I get sticky bolts at lesser charges even when cases have more volume and the primer pockets stretch out much faster with 2 or 3% of once fired primer pockets already loose .

I don't even know if they make LC cases with out dots any more . The latest cases I have with out dots are LC-12 . I have LC- 14, 15 17 all having the dots .

As for the 5.56 LC cases , I have several large lots of them . I'll take a look through some and see how different the patterns are . If they are different , I've not noticed a drop off in consistency/accuracy when loading same year head stamp with match loads in LC 5.56 brass . I'll update later what I find with my cases .
 
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Update

Yep the two large lots I looked at LC-14 & 16 have different dot placements . Not only that , some of the LC-14 cases even have different type crimps which would indicate they were not loaded at the same place or at minimum definitely not from the same lots loaded .

Thanks :rolleyes: , now I'll have to do case volume test to ease my mind :(

Note the case on the right has a staked primer .
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It's been discussed here before that the dots note which production line the case came from in case of a quality problem, 1, 2, 3, or 4.
 
It's been discussed here before that the dots note which production line the case came from in case of a quality problem, 1, 2, 3, or 4.

Yeah that's my basic understanding as well . The thing that gets me is the OP pulled those from the same box of ammo . I'd hope Fed/LC would at least not mix the brass from each production line . I mean how do they know if it's bad brass if they are mixed in the ammo box . The ammo has a lot number but I'm sure it does not indicate the line the brass was made on .
 
I read that in 2012, the production practices and specifications at Lake City were changed to bring their ammo in line with civilian factory standards so those factories could be tapped to contribute ammo in a wartime crunch. All the pressure equipment is now SAAMI-type conformal transducer stuff. That the brass is softer probably reflects what the civilian stuff does, too. Too bad, but that tells me you may now be better off with Starline's harder-than-223-alloy 5.56 than with new LC. Don't hold me to that, as I haven't measured it, but this makes me pretty suspicious.

I'm feeling like I lucked out when I bought 2000K of bulk new LC that was LC-11. Just under the wire.
 
UN , the softer cases I notice are with the 308 variety . I’ve loaded very little commercial 223 brass so I have no idea how it compares to Lake City then or now . I have almost exclusively loaded Lake City 5.56 brass for my AR . Then again as you know I have lots of LC brass . This means many of my large brass lots only have two firings at the most on them so I don’t really know how they actually hold up yet . I have one lot ...heck I don’t even remember the yea, , they have four loadings on them but I put those aside a few years ago with a note attached to anneal .
 
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Yes. I'm just assuming the 2012 change affected everything. The last new LC brass I got in 7.62 was a long time ago. I still have a good bit. It came from the CMP and is M852 LC 96, with the light cannelure just forward of the head. So it is good and hard a problem.

Atlas Development Group .308 W brass has double-struck heads to also make them hard. Starline .308 W brass is not as hard as military but was harder than any of the other commercial brands when BobCat45 measured it (we didn't have any ADG brass to compare at that time).
 
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