Small Rifle Primer Pocket Diameter

Discussion in 'Reloading Forum (All Calibers)' started by bigedp51, Nov 10, 2013.

  1. bigedp51

    bigedp51

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    I have a five gallon bucket of Federal .223/5.56 brass and after cleaning and prepping the brass I find out I have over sized loose primer pockets on 50% of these cases.

    Rather than seat the primers and find out the primer pockets are too loose I bought a pocket gauge. But one end of the gauge is .175 and the other end is .172, so I bought a .1745 pin gauge and decided to call this primer pocket maxim. The .175 NO-GO gauge end told me nothing, so I took it down to .174 and I was loosing a lot of cases so I ordered the .1745 pin gauge.

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    So I have four questions.

    1. Do any of you use pin gauges to check your primer pockets?
    2. What is your largets acceptable primer pocker diameter?
    3. Who makes the largest diameter small rifle primers?
    4. Is soft Federal factory loaded brass even worth reloading if the primer pockets are stretched after the first firing?

    I put a lot of work into these cases and I would like to used them but I do not want any high pressure gas leakage etching the bolt face or have any primers fall out.

    This is for loading AR15 rifles and I do not want the primers falling out and jamming the trigger group or damaging the bolt face. Normally military ammunition has crimped primers and on a over gassed AR15 the bolt can move to the rear while the cartridge is still gripping the chamber walls. And if your primer pockets are not tight you can pop a primer.
     
  2. jonbearman

    jonbearman I live in new york state,how unfortunate ! Site $$ Contributor

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    What I usually do is try all the different primers I have on hand and cci small rifle and tula seem to work on cases that were fired with hot loads to begin with.
     
  3. bigedp51

    bigedp51

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    I have Winchester, CCI and Remington and they are all about the same diameter. What is the diameter of the Tula primers I'm hoping someone makes a fat primer and all this brass doesn't have to be sold as scrap.

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  4. fredhorace77

    fredhorace77 Site $$ Contributor

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    i hate to send u three pages of info. but i have made the same exact mistake u have. http://forum.accurateshooter.com/index.php?topic=3823494.msg36275317#msg36275317

    the problem lies in the web area between the primer pocket and the internal case body. call it what u want but its the meat or lack there of where the flash hole sits that causes the problem to begin with. without adequate brass in this area the pressure of the fired round gets taken out on the primer pocket causing it to enlarge too much to hold the next new primer u intended on seating. .hate to say this but mine ended up being sold as scrap
     
  5. bigedp51

    bigedp51

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    fredhorace77

    I'm the one who told you how to make the two inch rod to measure web thickness and check for defective cases.

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    The cases I have pass this test, I'm looking to see if anyone has a max primer pocket diameter number and what company makes the largest diameter primers.

    At .1745 primer pocket diameter I can't push the primers out by pressing on the decapping rod with finger pressure below. This is used as a guideline for loose pockets at the AR15 forum. BUT the primer pockets are not as tight as new brass would be and I'm still looking and asking opinions about the maximum safe diameter size of the primer pocket for a autoloader before scraping the cases.

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    So again, who makes the largest diameter primers not on the list I posted above. Meaning does anyone have the diameter for Russian primers and CCI No. 41 primers?
     
  6. jlow

    jlow

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    Ed,

    That chart on primers is not completely correct. I have done some research on my own measuring Rem 71/2, Wolf SRM, and CCI400 using 20 samples each and an accurate Mito micrometer last year and their average diameters are 0.1749, 0.1750, and 0.1752 inch. The CCI400 are not very useful because of their thin cup but I have had very good luck using the Wolf in LC09 brass that had loose pockets (as per using the Rem 71/2) with the Wolf SRM primers. They are definitely bigger and much tighter.

    If your cull your pockets down to 0.1745”, the Wolf should work for you fine as my 20 primer sample had a max diameter of 0.1753” and min of 0.1746”
     
  7. fredhorace77

    fredhorace77 Site $$ Contributor

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    ok sorry about the confusion ..i understand what ur asking about now.
     
  8. bigedp51

    bigedp51

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    Thank you jlow, I wish I didn't have brass OCD, I culled them originally at .074 "BUT" I was even loosing once fired Lake City brass. So I resorted these cases and settled on .1745 because I couldn't stand scraping half a five gallon bucket of brass.

    I removed the crimps on all these cases using hand tools and in another forum a poster said he lost fewer cases using the Dillon swager tool and not removing brass. I think he my be right and the crimping process might be enlarging the primer pockets during manufacture.

    It bothers me that once fired Federal ammunition has brass that soft and to loose so many cases before you even have a chance to reload them.

    Don't be fooled the cases below do not have the NATO stamp on the base of the case and do NOT meet military requirements for hardness.

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  9. jlow

    jlow

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    Yea, that Federal brass is soft and yea not the same as those with the LC NATO stamp on them. Good luck with the project.
     
  10. expiper

    expiper

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    to all....here is my findings,,,,I have not measured any primers but go by feel,,,,I think the hardness of the primer cup has as much to do with it as the physical dims. ,,,,,,I am not a .223/5.56 shooter but have shot a lot of "B"enchrest and when my brass is new and tite' the WW small rifle seem to fit the smaller pockets (much easier to seat) and then once fire-formed and shot a cupla times the Fed 205's are perfect and then when "over" loaded or much used I go to Rem. 7-1/2's,,,,,I have nevr used any Wolf/Tula/etc but hear they are the biggest of all, so they should make use op the enlarged primer pokets,,,,,Roger
     
  11. bigedp51

    bigedp51

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    Does anyone know the diameter of CCI 41 primers?
     
  12. jlow

    jlow

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    Don't have it but one thing I did not mention about the Wolf/Tula primer is that I real reason I like them is they have given me some of the best ES/SD in MV that I have found.
     
  13. 37Lincoln1

    37Lincoln1

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    Ed,

    I just measured some and they were all at + - .1750
     
  14. bigedp51

    bigedp51

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    Thank you 37Lincoln1, my Remington 7 1/2 are the largest diameter primers I have to use with ball powders. I have CCI BR4 primers but I don't know if they will work well with H335, BLC2 and 748 ball powders. Its just practice AR15 ammunition loaded well below maximum for shooting holes in paper Zombies with my sons, and straining my bifocals.

    I will be reloading for my sons AR15 also and don't want his bolt face to look like below and have egg on my face. I have plenty of once fired brass so I just might raise the primer pocket standards for his ammo and keep the looser stuff for my ARs and just keep testing for acceptable diameter standards.

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