1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

when loading 223/556

Discussion in 'Handloading and Reloading' started by cemjr, Feb 19, 2011.

  1. cemjr

    cemjr Well-Known Member

    when, if ever, do you need to use magnum primmers ?
  2. hans471

    hans471 Active Member

    That depends on the brand of primers. With the Wolf primers "Magnums" are the recommended ones. With other brands....??? There is a lot of confusion and misinformation out there about the "dangers" of using magnum primers. Its not a simple subject as the manufactures themselves are not clear on what makes their primers "magnum". Now, Remington has a "small rifle" primer #6-1/2 that they tell you NOT to use in a .223 due to it being thin and not able to handle the pressure. They make a 7-1/2 primer that some books call "magnum" but that they recommend for .223. Go figure. Some say they only use magnum primers. Others say they use them in cold weather. One reference said, "Magnum primers may be helpful for ammunition that will be used in sub-zero weather conditions, but will rarely be necessary for general shooting needs." Note that they didn't say they should be used, they said they would rarely be necessary to ignite the powder.

    I saw some good tests where a guy did all sorts of loads with different primers to compare magnums and regulars. Truth is, there was hardly, if any, differences in velocity between the two. Some will swear that magnums will cause excessive high pressure build up as they ignite the powder much faster. Is that true? Your guess is as good as any.

    If you look at the amount of "fuel" in a primer compared to the amount of powder in a .223 there is a monumental difference in volume between the two. So, its hard to think that the primer can drastically change pressures. I have seen endless debate on this but have never seen any definitive proof one way or the other.

    Do what some of us have done, just do a web search and read countless opinions on this. After reading twenty or so articles you will be more confused than you are now.

    One point that many will make however is, if you start using ANY new component or load, start low and work your way up slowly from there.
  3. PapaG

    PapaG Well-Known Member

    No. No need for magnums for most loads in most calibers. stick with your loading manual recommendations. (I don't even think of them as recommendations, I think of them as law.) Probably why, after several million loads (commercial for 20 years, personal for over 40) I have never had a blowup or a misfire....and I have had a couple of commercial trap loads misfire.
  4. RustyFN

    RustyFN Well-Known Member

    They are recommended with W748 and H335 powders. I use both powders with standard SRP's with no problems and great accuracy.
  5. winchester1886

    winchester1886 Well-Known Member

    I use standard CCI primers in all my 223 loads and have for about 18 years. At one time I was using military brass and CCI # 41 primers.I ran out of #41 primers and couldn't find any so I contacted CCI and they told me to use CCI SR mag.primers that thet were the same except for cup thickness.
  6. GCBurner

    GCBurner Well-Known Member

    I mostly use Winchester primers, which say "for regular or magnum loads" on the box. Makes it simpler to stock.
  7. ArchAngelCD

    ArchAngelCD Well-Known Member

    That's only true for their Large Pistol primers. All other flavors come in both standard and Magnum.
  8. GCBurner

    GCBurner Well-Known Member

    You're right, I was just looking at the boxes on top of the stack, and didn't notice they were all LP. :) I don't really load for anything that requres a Magnum primer, anyway, other than the .44 Magnum, and the Winchester LP works fine for them.
  9. Gasitman

    Gasitman Well-Known Member

    I was sold magnums by a dealer here on accident. He told me just to use the least amount of powder the book said. So if it said 34gr-41gr, go with the 34. What I was told to use them up.
  10. ArchAngelCD

    ArchAngelCD Well-Known Member

    Sorry to disagree but i have to. If you are normally using a charge of 38.0gr with a standard primer in your load and want to match the velocity/pressure with a magnum primer you "might" have to drop the charge to 37.8gr, if that much. A magnum primer isn't so strong at to require you to use the starting charge to be safe. Of course when changing components it's always a good idea to work up your load again.

    During the shortage I was forced to use a lot of magnum primers in handgun ammo. All the load that were not at the top end of the pressure range were loaded as usual with no powder drop and all loads worked as before.
  11. Sunray

    Sunray Well-Known Member

    Magnum primers are about the powder used. They burn a bit hotter for a bit longer. They're for igniting hard to light powders and cold weather shooting. Some powders dislike the cold and get harder to ignite. Unless your manual says to use 'em, you don't need 'em. They have nothing whatever to do with the cartridge name either.
    "...told me to use CCI SR mag. primers..." That's because their "milspec" primers are nothing but a brilliant marketing gimmick for magnum primers.
  12. 788Ham

    788Ham Well-Known Member

    In my Hornady reloading book for .223, they specify SR Mag primers. These are the only primers I've ever used, no problems here!
  13. Redneck with a 40

    Redneck with a 40 Well-Known Member

    I use both CCI 400's and Wolf SRM's in my .223 loads, both work fine. I buy whatever I can find the cheapest.
  14. Ifishsum

    Ifishsum Well-Known Member

    I agree with Sunray, it mostly depends on the powder you're using. I tend to use them with ball powders like W748 and BL-C(2) and they do seem to offer more consistency - but that doesn't mean that a standard primer won't work either. You don't really need to use them in most cases.
  15. NCsmitty

    NCsmitty Well-Known Member

    I use CCI primers exclusively, in all my brass cases, and I keep it simple by using standard primers in loads using extruded and flake powders and magnum primers in all ball (spherical) powder loads. As mentioned, some ball powders can be harder to ignite in colder temperatures, under 32F, so working up those loads with magnum primers make sense.
    Really, any primer can be used with any load IF if you work up, using the proper methods. The question of consistency is another issue.
    What you don't do, is to substitute primers when using maximum or near maximum loads without backing off 2% or so and working back up.

  16. RustyFN

    RustyFN Well-Known Member

    Not a very good dealer IMO to tell you that instead of exchanging them for the right primers.
  17. bds

    bds Well-Known Member

    Maybe this will help.

    Different makes of primers will produce varying amounts of primer flash in size and duration. If you are using particularly difficult to ignite powder with smallest flash/duration primer in extremely cold temperatures, then you may need to use magnum primers.

    I recently started reloading for .223/.308 and these articles on primers helped me get "less confused". :D

    Primer chart and specs (covers primer cup thickness and burn characteristics) - http://www.sksboards.com/smf/index.php?topic=56422.0

    Primer burn comparisons (photos of primer flash). Article also has links for very comprehensive small/large primer comparison articles that include chamber pressure measurements of different primers and statistical SD/ES data - http://riflemansjournal.blogspot.com/2010/08/primers-wolf-223-primer.html

    Grab a nice big cup of coffee and enjoy the articles. :D
  18. ssyoumans

    ssyoumans Well-Known Member

    I almost always use CCI Small Rifle Magnum primers, and Speer recommends them for some harder to ignite powders like W748, BLC-2 & Varget.

    I have used CCI standard with TAC & AA2230 without any issues.

    For the most part, I just develop my loads using SR Magnums, I only have the regular ones because I accidently picked up the wrong ones on the shelf and had a few powders that don't list using Magnums.
  19. cemjr

    cemjr Well-Known Member

    In regardes to std primmer vs mag primmer and powder burn rates; My Lymans 49TH manual lists 15 differant powder selections for a 63gr jacketed smp (for example). On the burn rate chart they vary from 60th to 80th with 60 being the fastest and 80 being the slowest and all using a remington 7 1/2 small rifle primmer. This seems like a wide range of burn rates using a std primmer? So how slow of powder would you need to use before you would need to step up to a mag primmer?
  20. cemjr

    cemjr Well-Known Member

    W748 = 77th, BL-C2= 75th

Share This Page