I will try to get a picture in the daylight.

My daughter helped put a couple hundred rounds through the rifle.
We used current production IMI M193 and M855 without blowing primers.

I don't know if it makes any difference, but the bolt carrier is of the old Colt half moon type.

I used calipers on the firing pin and it matches the one in my spare upper.
The firing pin retaining pin is not bent.

It appears there may be some minor additional pitting in the dark discolored circle, but nothing I would be concerned about.

There is nothing wrong with the bolt then?

quote:

Originally posted by lbj:
There is nothing wrong with the bolt then?

I do not believe so. The bolt face isn’t finished very finely to begin with, and therefore it’s hard to know if the pitting in the discolored ring is unusual, but if it is, it’s very minor.

I just checked a couple of my bolts. They’re in Colt rifles and the bolt faces are smoother than yours. One has about 5000 rounds fired, and the other less than 700 rounds. Both have the discolored ring around the firing pin hole that marks the edge of the primer pocket when a round is in contact with the bolt, so the discoloration evidently forms pretty quickly. I’ve never experienced a blown primer with either rifle.

My 700 round bolt doesn’t exhibit any pitting inside the ring, but the 5K bolt does show a little. It’s not as pronounced as what I see on your bolt face and it’s only part way around the circle, but it definitely exists. I don’t, however, know what would cause pitting there if gas isn’t escaping around the primer and cutting the bolt face. I’ve sometimes seen case polishing compound build up in the crack between the primer and the edge of the case primer pocket, so that may contribute to the discoloration and wear.

Again, I personally would not be concerned by what I see on your bolt. In my opinion it would not have any adverse effect on reliability or safety.

The Colt bolt in my spare upper is a lot smoother, though not perfect and it's new.

My,my,my. I've been following this thread passively knowing that I had a batch (200) of the same ammo that I picked up from PSA in mid August. As I looked at the boxes prior to posting this I see mine are from the same lot number posted in the title.
First box, loaded 20 rounds and about ten rounds in the trigger went "click". Broke it down and found an un-fired round partially/mostly in the chamber. Primer not dimpled. Got the round out, reinserted the magazine and same result with next round. At this point I was recalling this thread and thought POS Independance, I won't be buying you any more. Pulled out a box of known good Wolf Gold. First pull, same result. Now the head scratching began. At that point we noticed (3) separate shell casings on the ground with blown primers.
Broke the rifle down again, looked in the trigger assembly and didn't see any primers...
It turns out one of the primers got wedged into the chamber and got smooshed in there keeping the subsequent rounds from fully loading.

Imagine my surprise when I pulled my box and noticed it had the SAME lot number listed here.

Three rounds out of the first fifteen...
Barrel is a LaRue PredatAR with a Wylde 223 chamber. Everything else including BCG is Bravo Company.

I appreciate the confirmation.
Yep, bad lot.
It bites moose, doesn't it?

Have y'all contacted them yet? Ammo companies are usually very good at making things right and they really need to be notified so they can get the word out too.

Yes it does suck moose balls lbj.

quote:

Originally posted by leavemebe:

quote:

Originally posted by lbj:
It's not exactly the good kind of club to belong to.

quote:

Originally posted by NikonUser:
A metric ton of 5.56 ammo? How much is that?

Well, let's see. 55gr for bullet, 80gr for case, 25gr for powder and 10 grain for primer, That's about 170grain per round. (Note to self, next time you charge some cases, weigh a 55gr loaded cartridge, if you have any.)

At 7000 grains per pound, we get about 41 cartridges per pound. A metric ton is 2,200 pounds, so a metric tone of that ammo will be 90,200 cartridges. That represents a sizable investment.

Now that is funny right there.

Well, I am an Ammoholic

The net weight on a 1200 round case of IMI M193 is 14 kg. That works out to a mere 71.42 cases or only 85,704 rounds if that is what I used most of the time. I don't see a problem .

Again, I hope IMI/Federal will make this right for you. I don't have any Independence ammo left and won't be buying anymore.

Been away for a little while and forgot about this thread.

Glad to see the estimate off the top of my head wasn't that far off. I never did get a chance to weigh a 55gr cartridge; I don't have any. All my non-match stuff is 77gr ammo.

I read through the whole thread again and it's definitely the ammo; classic signs of grossly excessive pressure. There should be no damage to the firing pin as that usually only occurs if you pierce the primer; something easy to do if you make a mistake and use the wrong primer, like a Remington 6 1/2. Ask me how I know. Always good to have spare FP for your AR; they only cost $5. Or used to.

Sigfreund provided some great thoughts, as he usually does, and the unfired case (not cartridge) length would have been interesting to check. Best way to do that would be to pull the bullet and use a caliper. The COAL is not an issue because it has to fit in the magazine and you are using other ammo just fine. The one difference would have been in the ogive shape, where the maximum diameter starts earlier that normal, but I doubt that. That alone would not have caused that much over pressure.

It could also be combination of things, but my money is on an out of spec cartridge load with a tight chamber. I'm surprised Independence didn't take it back, but it's good to get rid of it.

quote:

Originally posted by lbj:
As I suspected, the local PD was more than happy to take the Independence 5.56 off my hands.

Therefore, it has been disposed of.
I did include a note and a spent case with blown primer.

LBJ - I'm going to try this with the remainder of mine. Any suggestions on where to direct the initial phone call within the dept.?

I called the non emergency number of the local PD and asked if they would take it.
She said the bomb squad guys would love to have it.

I just bought some of this before this thread came out. It's a different lot number. I haven't got a chance to shoot any of it yet but I really hope it's okay and just the one lot that was bad, I really can't afford to toss it.

I am keeping mine. The stuff I have is between 3-5 years old, if the year is part of the lot number. I have already shot close to 1000 rounds of the stuff with no issues. And, I have over 1000 rounds of it left. I suppose I won't buy anymore. But, I have been satisfied with what I have shot up til now...

Sorry to revive this older thread but a heads up for everyone I contacted Federal and I'm sending them a sample of 60 rounds to test. I had the same issue reported here with my first couple boxes. He said this was the first report of this issue on this batch to which I replied a quick internet search yields this is hard to believe. He was reluctant and after debating with the tech rep on why my CMMG complete upper on a PSA lower "custom" build won't cause blown primers because the "buffer spring timing" may be off, or that I don't need a gunsmith to clear my "custom build," and also that my chamber is 5.56 and not Wylde and CMMG didn't dupe me with stamping it 5.56 if it wasn't he agreed to sample some. It'll be picked up Tuesday and tested within 3-4 weeks. With how this rep was I'm not confident it'll get resolved but we'll see I guess.

quote:

Originally posted by parabellum:
That's Lake City ammunition, isn't it?

Yes

https://www.youtube.com/watch?v=YIB8aItfIx0

quote:

Originally posted by FDEinAZ:
With how this rep was I'm not confident it'll get resolved but we'll see I guess.

Thanks for all that. Please keep us posted.

I am not, however, surprised by the lack of enthusiastic cooperation.

quote:

Originally posted by FDEinAZ:
Sorry to revive this older thread but a heads up for everyone I contacted Federal and I'm sending them a sample of 60 rounds to test. I had the same issue reported here with my first couple boxes. He said this was the first report of this issue on this batch to which I replied a quick internet search yields this is hard to believe. He was reluctant and after debating with the tech rep on why my CMMG complete upper on a PSA lower "custom" build won't cause blown primers because the "buffer spring timing" may be off, or that I don't need a gunsmith to clear my "custom build," and also that my chamber is 5.56 and not Wylde and CMMG didn't dupe me with stamping it 5.56 if it wasn't he agreed to sample some. It'll be picked up Tuesday and tested within 3-4 weeks. With how this rep was I'm not confident it'll get resolved but we'll see I guess.

Is this from the same lot number?

Anyone had or heard of any issues with anything other than the FC16B001-169 lot that's eating el-beej's lunch? I have a few hundred rounds of their FC16B001-172 lot and now I'm skeered to light 'em off.