Popped Primers - .308

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  • Rating - 100%
    44   0   0
    Nov 23, 2008
    2,742
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    Mishawaka
    I have a conundrum with trying to figure out why these primers popped out under fire. I shot these from a Savage 10 FCP .308 rifle.

    Recipe:
    Federal Gold Match Brass
    Winchester LR primer
    H4895 powder
    42.3 to 43.1 gr load
    168 gr Hornady Amax bullet

    I contacted the person i got the brass from and he claimed he had no idea how many times it's been fired which leads me to believe that maybe the primer pockets were too loose. I loaded the primers with a Lee hand prime and they "seemed" snug but since this is the first time i've loaded large rifle primers i'm not sure.

    I also double checked the powder charge from my ChargeMaster to my beam scale and they checked out good.

    My question is there any other variable that might cause the primers to pop out besides a loose primer pocket ?

    Side Note: the powder loads i used are in the middle of the spectrum for this powder so this shouldn't be the culprit.

    2195bf7d.jpg


    Here is the target from the 42.7 gr load i used.

    e910f0e2.jpg
     
    Last edited:
    Rating - 100%
    44   0   0
    Nov 23, 2008
    2,742
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    Mishawaka
    I forgot to mention that I shot 12 rounds of factory Federal Gold Match with no signs of popped primers. From what I can find on the internet it looks as if FC brass is kind of known for this. Anyone know how well the LC brass performs ?
     

    djl02

    Expert
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    1   0   0
    Sep 18, 2009
    1,406
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    Indiana
    Sounds like loose pockets. I have had new FGMM ammo do this in a semiauto. One out of every 3 shots. They wanted the ammo back,and the code date it was run. Makes a mess of things,one primer got caught brhind the carrier and scarred up my reciever,which,Bushmaster replaced.
     

    Yeah

    Master
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    2   0   0
    Dec 3, 2009
    2,637
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    Dillingham, AK
    There are extractor impressions on all of them, and several of the cases with primers in place are sooty and flat. I'd expect your bolt face is or soon will be etched.

    You are over pressure.

    It might be that some of the cases also have loose primer pockets, but you are over pressure none the less.

    By what data are you 'middle of the spectrum'? How far from the lands?
     
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    44   0   0
    Nov 23, 2008
    2,742
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    Mishawaka
    .020 from the lands and Hodgden says the minimum charge is 41.0 gr and max is 45.4 gr for the 168gr Amax bullet.

    I loaded my test loads between 42.3 and 43.1, those pressure are well within limits.

    If you noticed two of the cases have gas blow by around the primers which tells me the primer pockets are suspect. I have to agree that the primers do looks a tad flat.

    The gun itself has about 200 rounds fired.
     
    Last edited:

    billybob44

    Master
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    383   0   0
    Sep 22, 2010
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    In the Man Cave
    Before you "Trash" that FC Brass...

    Buy/try a 100 pack of Wolf/Tula primers in those FC cases.
    This is NOT a cure for loose primer pockets, but MAY get a few more cycles through those FC cases??

    Wolf/Tula primers do seat tighter on most all sizes of primer pockets. I have had some .223 FC cases that CCI #400 primers were a tad loose, and the Wolf .223 primers were tighter to seat, and I got a few more cycles through those FC cases?? Worth a try..Bill.
     

    Mortblanc

    Plinker
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    Jul 3, 2012
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    .020 from the lands and IMR says the minimum charge is 41.0 gr and max is 45.4 gr for the 168gr Amax bullet.

    I loaded my test loads between 42.3 and 43.1, those pressure are well within limits.

    If you noticed two of the cases have gas blow by around the primers which tells me the primer pockets are suspect. I have to agree that the primers do looks a tad flat.

    The gun itself has about 200 rounds fired.

    My Hornady Book, 8th Edition lists 43.3 as max with IMR 4895!!!

    You are getting close and always remember, each load is subject to the varitations of the individual rifle.

    I would start over with fresh brass/primers and work up to the load slowly.
     
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    44   0   0
    Nov 23, 2008
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    Mishawaka
    Was it super hot out w/ your rounds in the direct sunlight by any chance?

    It was in the 80's outside and I had the ammo in a plastic box in the shade under the roof that's over the benches.

    My Hornady Book, 8th Edition lists 43.3 as max with IMR 4895!!!

    You are getting close and always remember, each load is subject to the varitations of the individual rifle.

    I would start over with fresh brass/primers and work up to the load slowly.

    I agree, I'll start with some different brass and reduce the charges starting low and work it up watching the primers for flattening.
     

    kludge

    Grandmaster
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    5   0   0
    Mar 13, 2008
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    A few comments...

    Are you hand priming? Get to know what is a normal feel and then you can recognize it when the primer goes in too easily, indicating that the pocket is loose (meaning the case head/web area has expanded - not good).

    Yes, Federal .308 Win brass is notorious for being soft and getting loose in the pockets; I personally don't reload Federal .308 Win brass, unless it's for "plinker" low-pressure loads. A wise man told me once to buy a 0.0001" micrometer. Then if you buy new brass (or new factory ammunition) you can keep an eye on the diameter of the case head/web area. The web of the case is hardened and should not grow at all if pressures are in the normal range.

    Next, the Hodgdon/IMR data is for the Sierra 168gr bullet. Might matter, might not, but as posted, Hornady has different numbers. But what really matters is your rifle.

    Which is why it's very helpful to have a chronograph. Next to my press, it's probably my most important tool for hand loading ammunition. Velocity is directly related to pressure. All else being equal, if you get to max velocity before you get to max load, you must be VERY cautious. I've hit max velocity on the recommended START load before.

    Lastly, when you fired the first one that the primer fell out of, why did you keep shooting? That's a good way to lose an eye or other important parts. Also, was your bolt hard to lift after shooting these rounds? Reading primers is very "hit or miss" when indicating chamber pressure. Here is a good primer on pressure signs... Pressure Signs - Shooters Forum

    Be safe out there.
     

    IndyGunworks

    Grandmaster
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    25   0   0
    Feb 22, 2009
    12,832
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    Carthage IN
    I can't even begin to answer this. :facepalm:

    Why not? If you are starting low and working your way up it doesnt really matter how many firings are on the case. If they pass a visual inspection and primers seat w/ some degree of resistance, i dont care how many times its been fired either.

    I couldnt tell you how many firings are on ALOT of my brass. they just get a casual glance over as they get fed into the machine. If the necks are spit or case bulged or anything that doesnt appear normal they get tossed. Some cases have 20 firings some have 3.
     
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    4   0   0
    Nov 19, 2009
    2,191
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    Central Indiana
    Why not? If you are starting low and working your way up it doesnt really matter how many firings are on the case. If they pass a visual inspection and primers seat w/ some degree of resistance, i dont care how many times its been fired either.

    I couldnt tell you how many firings are on ALOT of my brass. they just get a casual glance over as they get fed into the machine. If the necks are spit or case bulged or anything that doesnt appear normal they get tossed. Some cases have 20 firings some have 3.

    1. It doesn't *sound* like the OP has nearly the experience needed to know if he's getting proper primer feel

    2. He's using brass that's known to loosen primer pockets extremely fast

    3. He's not "working up slow". He's pushing up to .2gr under Hornady's book max for his particular bullet. I don't have the book handy right now but i'm willing to be he's not using the exact components that were used to develop that book load.

    4. He's using IMR4895, which while being one of my favorite powders, is temperature sensitive and like just about all powders, displays lot-to-lot variation in burn speed that might be putting him overpressure at his near-max starting load.

    If you don't want to keep track of your firings on YOUR brass in YOUR guns I don't blame you. I have some .30-06 brass that i've completely lost track of and don't mind in the least - it meets my inspection criteria and the primers seat like brand new brass. However, the OP could likely be loading brass that someone else already deemed ready for the scrap pile and not know it. Its it worth losing an eye or part of your face to save a few bucks on brass, when you could just buy new brass and likely get 20+ firings out of it ?
     
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    44   0   0
    Nov 23, 2008
    2,742
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    Mishawaka
    I've already scrapped the brass and I have 60 casing I know are once fired factory brass. I'm going to start my next set of loads using these for sure. I'm going to start much lower on my charges at around 39.5gr and work up to about 41.5gr and see if there's a nice middle ground in there for accuracy.

    I'm certainly not looking for a barn burner load but more of a accurate load. My initial aim was to find something in the 2,650 fps area and i did and it also proved accurate but yet over pressured.

    My mistake and well learned from.

    I also found that the lands are further out than initially thought. Their located at 2.845 so i'm going to setup the OAL at 2.830 instead of 2.800

    This should relieve some of the pressure and also locate the bullet closer to the lands.
     
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    44   0   0
    Nov 23, 2008
    2,742
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    Mishawaka
    Well fellas, it's looking darn good now. As i stated i changed a couple things to calm down the beast. I lengthened the oal and reduced powder charges and used known once fired brass. Sad part is with 3 different changes i won't know for sure what happened yesterday but my educated guess would be over pressure. This just proves don't always go by manufactures recommended data and always start low.

    "I know", I should have known this (which i did) and bone headedly ignored. Hmm, headedly, is that even a word! LOL ....

    Recipe used:
    Once Fired FGM brass (Neck sized since they were fired from this rifle)
    Hornady Amax 168gr bullet
    41.0gr & 41.5gr of 4895
    2.835 OAL (.010 off the lands)
    Winchester Primer

    These loads appeared to be more tame. I fired a group of 39.9gr, 40.5gr, 41.0gr and a 41.5gr load. Primers appeared in good shape with each string, brass came out of the chamber easy and accuracy was descent with the 41.0 and 41.5 load. The first two loads suffered accuracy for sure.

    Looks like i have a good foot hold on where to tweak the powder amounts now and see what i can do.

    d0d2a2a7.jpg
     

    IndyGunworks

    Grandmaster
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    25   0   0
    Feb 22, 2009
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    Carthage IN
    1. It doesn't *sound* like the OP has nearly the experience needed to know if he's getting proper primer feel

    2. He's using brass that's known to loosen primer pockets extremely fast

    3. He's not "working up slow". He's pushing up to .2gr under Hornady's book max for his particular bullet. I don't have the book handy right now but i'm willing to be he's not using the exact components that were used to develop that book load.

    4. He's using IMR4895, which while being one of my favorite powders, is temperature sensitive and like just about all powders, displays lot-to-lot variation in burn speed that might be putting him overpressure at his near-max starting load.

    If you don't want to keep track of your firings on YOUR brass in YOUR guns I don't blame you. I have some .30-06 brass that i've completely lost track of and don't mind in the least - it meets my inspection criteria and the primers seat like brand new brass. However, the OP could likely be loading brass that someone else already deemed ready for the scrap pile and not know it. Its it worth losing an eye or part of your face to save a few bucks on brass, when you could just buy new brass and likely get 20+ firings out of it ?

    That makes a TON of sense and I would have understood completely what you were trying to say if thats what you would have said to the OP in the first case. But you didnt mention anything about working up a load or any of the other stuff. ALL you said was...............

    You loaded brass that was fired and reloaded an unknown number of times??????????? :dunno::dunno::dunno::dunno:

    Implying that the acting of loading brass and firing it that you didnt know how many times it had been previously reloaded was the issue, and not all the other details in which you spelled out in the second post.



    All that being said, i think first thing i have you quoted saying in this post is EXACTLY the issue. Starting .2 grains under the book max is a BIG no no
     
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