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  1. #16
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    Quote Originally Posted by cjd3 View Post
    I have a set of .223 Go No Go Guages you can borrow. Let me know if you are interested. I have no need for them in immediate future, so if anyone else wants to borrow them, lemme know.
    I really appreciate that. Does it matter if it's a 5.56 chamber? I can't remember if a .223 gauge is compatible, but it seems like it would be.

    Quote Originally Posted by Stone View Post
    Definetly wont hurt to check headspace, If you can borrow them from CJ.(very generous offer BTW!) Yeah you got a batch of bad ammo which could also have some overly soft brass. I would set that stuff aside now since its a known issue. I would take the problem child and give her a full strip down and cleaning. Get into the extractor claw, the bolt face and the barrel extension with your dental pics and Q-tips as you may have excessive brass shavings everywhere impeding performance. Check down in the trigger well to for popped primers. Give it a solid lube job, I run my rifles wet and they seem to do very well. Load up a mag or two of some good ammo and see how it does. Keep an eye on its extraction to at this point as well. If you still have the heavy scrape marks just swap out the bolt with a new one and see how it functions. Hopefully this will narrow it down to a specific point... This all goes to show how important it is to inspect your spent shells once in a while...

    ETA: When your stripping it down or putting it back together, look over everything real well. Sometimes we forget that stripping down and cleaning a rifle is always the best oportunity to inpect parts for excessive wear and not just a time for cleaning. Myself included...
    All good stuff. Unfortunately I've done 95% of that. I've broken down the bolt and scraped out the extractor and nothing found there. There was a tiny bit of brass in the extractor pocket, but not in a place to impede movement. Lower had no primers. The only thing I didn't do was hit the barrel extension with a dental pick...that's easy to go do. Otherwise it was cleaned as well. My last post "update" post with the picture was after all of that. As I said, bolt was swapped out with positive results. I think at this point, it's time to track down a spare extractor and headspace (for good measure).

    Or just shoot the damn thing, because it functions fine, otherwise.

  2. #17
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    From my research, the headspace is the same. For the helluvit, Iím checking headspace today since I have nothing better to do.

    Also, your inbox is full.

  3. #18
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    Quote Originally Posted by cjd3 View Post
    From my research, the headspace is the same. For the helluvit, I’m checking headspace today since I have nothing better to do.

    Also, your inbox is full.
    I think I cleared some PMs out for it to work now.

  4. #19
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    To get an accurate reading on a 556 chamber, you would need a set of 556 guages.

    223 rem guages of certain brands are on the longer end of the spectrum. So closer to 556.

    The throat s just a hair longer, as why most times 223 rem in a 556 chamber is no problem, it’s the 556 cases that are a smidge longer, have the notes somewhere in my reloading notes.

  5. #20
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    Quote Originally Posted by mustangfreek View Post
    To get an accurate reading on a 556 chamber, you would need a set of 556 guages.
    From my research, I believe you are referring to a throat gauge. Like cjd said, according to the internet (and yes, I take it with a grain of salt), a Go/No-GO/Field gauge is the same for .223 and 5.56. But I welcome evidence to the contrary.

  6. #21
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    Gator,

    Watch this video if you want. 12 minutes or so about the difference between 223 and 556.

    https://youtu.be/VCS4fXFmCyA

  7. #22
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    Based on that video and the fact that you were shooting heavy bullets for caliber it leads me to think this is probably the most likely cause.

    Meaning that chamber might be one of the hybrid type and you were definitely shooting 5.56 brass so the added few thousands on the brass plus the heavy bullet probably caused your problem.

    Throw in the chamber dimension and that solves it in my mind.
    Last edited by alamo5000; 29 September 2019 at 15:14.

  8. #23
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    Quote Originally Posted by alamo5000 View Post
    Based on that video and the fact that you were shooting heavy bullets for caliber it leads me to think this is probably the most likely cause.

    Meaning that chamber might be one of the hybrid type and you were definitely shooting 5.56 brass so the added few thousands on the brass plus the heavy bullet probably caused your problem.

    Throw in the chamber dimension and that solves it in my mind.
    Can you be a little more specific about what it is you're talking about? Which problem do you think is solved, in your mind?

    The barrel is a 5.56 barrel (V7) and the scraping issue happens regardless of bullet type (length/weight), but not universally (different bolt, no scraping).

  9. #24
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    I started with the biggest problem first. Popping primers is not good. Its definitely not safe so that's where I began then I worked backwards.

    Basically to me where I would start looking is at the chamber of that specific barrel. It would explain a lot if someone can look at it and measure etc.

    If you watch that video he goes into some of the different length and whatnot measurements of 5.56. If you add all that up and then throw in a larger bullet with a different Ogive it can easily explain why that ammo works in one gun but pops primers in that one. Basically that all boils down to the chamber and/or throat dimensions are tight for that manufacturer (or on that given day that it was made or whatever).

    My theory is that the chamber is too tight and all the tolerance stacking from the barrel itself to possibly the brass and bullet combination is leading to a dangerous situation. Little things like the bolt tolerances or the wear on the carrier or gas rings become amplified in importance. Basically it sounds like that rifle is operating at the top edge of 'safe' and it is most likely how they reamed the chamber and whatnot.

    That would also explain why you not only blew primers but also are getting swipe marks on all your brass. Those swipes no matter how big or small are from pressure so those swipes plus the blown primers they keep on leading me back to the whole chamber tolerances thing. The bolt might be a thousandth here or there but still within tolerance. If the chamber is overly tight it makes that window of tolerances for the bolt razor thin.

    If you can shoot that same ammo out of another rifle without cratering or blowing the primers (especially on crimped 5.56 brass) then that to me has to be it. It would explain the swipe marks across the board too.

    I would probably wager you a beer on it. If you take it to someone that has the ability to measure and examine that-- if I am wrong I will buy you a beer of your choice.

  10. #25
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    Quote Originally Posted by gatordev View Post
    Can you be a little more specific about what it is you're talking about? Which problem do you think is solved, in your mind?

    The barrel is a 5.56 barrel (V7) and the scraping issue happens regardless of bullet type (length/weight), but not universally (different bolt, no scraping).
    Also sorry for the first response. I typed it on my phone so I wasn't clear.

  11. #26
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    Quote Originally Posted by gatordev View Post
    From my research, I believe you are referring to a throat gauge. Like cjd said, according to the internet (and yes, I take it with a grain of salt), a Go/No-GO/Field gauge is the same for .223 and 5.56. But I welcome evidence to the contrary.

    Yes the 556 has a longer throat /freebore

    Well if our just roughly checking, the 223 guages might help. As a lot of times 223 go guages are roughly the same, itís the 556 no go guage thatís longer then the 223 guages. so in some instances a 223 no go will close on a 556 chamber, which tells ya...not much...lol.

    Again if just wanted to make sure itís ok, a colt field guage will let ya know. But your instance sounds tight..

    Of course theirs other ways to figure out exactly your chamber dimensions, just need a few tools

    Found this pic referring to the differences in guages
    Attached Images Attached Images  

  12. #27
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    Alamo, I get what you're saying, and it's possible that, at the end of the day, that is part of the issue. But...

    Quote Originally Posted by alamo5000 View Post
    If you can shoot that same ammo out of another rifle without cratering or blowing the primers (especially on crimped 5.56 brass) then that to me has to be it.
    That's not what's happening. As I've mentioned, the ammo popped primers out of two different rifles and the "problem" rifle isn't popping primers on other 5.56 brass.

    If you add all that up and then throw in a larger bullet with a different Ogive it can easily explain why that ammo works in one gun but pops primers in that one.
    Again, that's not exactly what's happening. It shoots other 77gr 5.56 fine.

    I can see where the tolerance stacking may come into play, since with a different bolt, the scraping goes away. I think another thing I need to try is put the "problem" bolt in Rifle C (known good rifle) just to see what happens, since Rifle C's bolt worked fine in the "problem" rifle.

    As always, it's a matter of having the time to mess with all this stuff.

  13. #28
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    I just found this. Headspace Gauge and the AR.

  14. #29
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    Coinkydink.
    There's no "Team" in F**K YOU!

  15. #30
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    Quote Originally Posted by mustangfreek View Post
    Yes the 556 has a longer throat /freebore

    Well if our just roughly checking, the 223 guages might help. As a lot of times 223 go guages are roughly the same, it’s the 556 no go guage that’s longer then the 223 guages. so in some instances a 223 no go will close on a 556 chamber, which tells ya...not much...lol.
    My apologies, Mustang. I did some more reading last night and found some more info that goes right along with what you're saying (and now cjd's link above). Thanks for pointing it out and making me dig deeper.

    I just found this. Headspace Gauge and the AR.
    That's good stuff. I think I'll give your gauges a try and see where it stands, but grab some 5.56 gauges to have. I should have bought them a long time ago, but they were always out of stock.

    We'll see what they all say when I play some more with the rifle.

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