Mil-spec FMJ vs Civ FMJ and TMJ vs CMJ

Discussion in 'Ammunition & Reloading' started by Secondhand_Hero, May 25, 2014.

  1. Secondhand_Hero

    Secondhand_Hero New Member

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    Hello, users! This is my first time on in a long while (due mainly to my own lack of knowledge and desire to better acquaint myself with firearms in general) and what has brought me back is the lack of information, and worse yet, MISinformation, about the differences between these rounds around the interweb.

    Now, of course, FMJ's (or at least civ-spec) have exposed lead on the ass-end of munitions whereas TMJ's do not, meaning that TMJ's are more user-friendly in terms of lead poisoning but this is about as far as i have been able to get in my research.

    i have read that Mil and Civ spec FMJ's differ in terms of Mil having generally thicker jackets and more uniform builds while more closely resembling a standard TMJ in terms of modeling (due to Gen Convention) but i don't know how much of that is true.

    As for TMJ vs CMJ, is there a difference at all? Are they the same beast under different names?

    Also; ballistics, reliability, quality, and overall performance comparisons would be swell~

    Thank you in advance for all of the help, friends!
     
  2. JonM

    JonM Moderator

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    depends on who is making the bullet.

    military 55grain fmj is pretty shoddy stuff. ive shot a lot of it and reloaded a lot of it sourced from pulled ammo. jacket thicknesses vary greatly and is often visibly not concentric.

    most civvy 55grain follows this pattern.

    it works decent enough out to 300yards and is really good for defensive use.

    if you want an accurate bullet the sierra matchkings are superb.
     

  3. Professor

    Professor New Member

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    Speaking of pulled ammo (question directed toward Jon), how IS pulled ammo? I see a lot of it for sale, but am not sure how "damaged" it is from the pulling process. (These bullets would be used for general plinking and target practice at no more than 150 yds.)
     
  4. Axxe55

    Axxe55 The Apocalypse Is Coming.....

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    you can use a collet style puller that mounts in place of a die in your press or an inertia type to pull it out of the case.

    now how they pull them commercially in large lots, i not for sure what methods they would use.
     
  5. JonM

    JonM Moderator

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    perfect for your needs. its what i use pulled ammo for

    they work just fine. ive got about 500 175grn m118 air pulls for the 308 from milsurp sniper ammo. not as good as sierra 168 match kings but still a nice sub to 1 moa bullet.

    military ammo is not as consistant as civilian stuff but its cheap and very good for plinking and training. the only reason its cheap is because we the people paid about 4 times its value to produce it then paid someon else to dispose of it...

    just because something is military doesnt always mean its the best. this is especially true with ammunition. almost all military ammo is vastly inferior to civilian ammo. if ammo companies dont produce a good product it wont sell well. government run anything is usually shoddy and bottom barrel.

    if you want quality, cheap prices, resoponsive service private sector is the best place. if you want high priced junk just hand out a government contract.
     
    Last edited: May 25, 2014
  6. Secondhand_Hero

    Secondhand_Hero New Member

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    Well it sounds to me like you're also hinting towards which of the two (between Civ and Mil-spec) FMJ's are a more reliable choice in terms of performance!
     
  7. Mercator

    Mercator Active Member

    Between TMJ and FMJ there is a difference without distinction. In TMJ everything is "encapsulated", so the primer will not release vaporized lead in your face. That's CCI's marketing claim. In reality, lead poisoning from shooting FMJ is rare as hen's teeth, possibly nonexistent. In that sense, TMJ is a cure looking for a disease. I don't know every intricacy of their manufacturing, only that CCI errs on the side of hot air.
     
  8. JonM

    JonM Moderator

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    yup. in general civilian bullets will perform better. if you need tracer explosive components armor piercing etc thats where military ammo is better. in terms of accuracy civilian bullets win.
     
  9. Secondhand_Hero

    Secondhand_Hero New Member

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    That's more along the lines of what i was taking from past forums read; along with a possible wear to the case due to the dispelled lead that normally leaves the case flat.. That and from the hard contact of a TMJ it can lead to a quicker wear on either the barrel or the firing pin.. Any thoughts on either of those?

    Also, do you know if there is a difference between a Complete Metal Jacket and a Total Metal Jacket? i believe they are simply different names for the same thing when looking at the basic construction of the two but i'd hate to make the assumption off of a basic understanding.
     
  10. Professor

    Professor New Member

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    1st) Thanks for the clarifications on pulled bullets.........2nd) regarding TMJ being safer: well yeah, it is....BUT....I think that the danger from exposed (to burning gases) lead is SLIGHTLY over stated, and just another reason used by the anti-gun crowd to ban shooting or indoor ranges.
    Whenever I melt/cast lead I do it outdoors, but I don't lose sleep if I shot some NON-tmj rounds indoors.
     
  11. Mercator

    Mercator Active Member

    Simply, no studies exist that prove the benefit of shooting TMJ. Had there been any, CCI Speer would have likely made references to them on every box. On the other hand, common sense tells us, no harm in the TMJs for the same price as FMJ.

    The common concern about lead poisoning is played up often to sell products. Truth in advertising does not require that they distinguish LEAD COMPOUNDS (toxic) from ELEMENTAL LEAD (largely inert), but doing so would be nice wouldn't it.
     
    Last edited: May 26, 2014
  12. JonM

    JonM Moderator

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    Lead poses no health risk unless it is disolved into a liquified form via a chemical process and absorbed through the skin or ingested. If lead is gassified by heating it poses a health risk.

    I prefer to shoot tmj bullets over exposed lead because its easier to clean the bore later. You don't have lead building up with copper. Tmj bullets tend to be more aerodynamic as well. Tmj have a greater chance of retaining the jacket on impact than lead based bullets do.

    Lead smelters for casting don't get hot enough to gassify lead but there are other chemicals and fumes that come off fluxing lead you don't want to breathe.
     
  13. robocop10mm

    robocop10mm Lifetime Supporting Member Lifetime Supporter

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    Actually the terms TMJ and CMJ are misnomers, They are not jacketed, they are thickly plated. It is not possible to COMPLETELY jacket a bullet. TMJ more concentric than plain FMJ.

    And, the primer does not "release" the lead from the base of the bullet, the primer CONTAINS lead.
     
  14. robocop10mm

    robocop10mm Lifetime Supporting Member Lifetime Supporter

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    I do not know who told you this information, but WTH? Wear to the case? Dispelled lead? Hard contact of a TMJ? Hard contact to what? What is this going to wear? How does a firing pin get worn by a bullet?

    If someone is actually telling you stuff like that, NEVER SPEAK TO THAT PERSON AGAIN!!! They should not be allowed anywhere near a firearm, ever!
     
  15. Mercator

    Mercator Active Member

    Yes, the primer contains lead. When the primer burns, it releases lead in your face. I referred to it as CCI's marketing. "Base of the bullet" was nowhere in the context.
     
    Last edited: May 26, 2014
  16. Secondhand_Hero

    Secondhand_Hero New Member

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    Again, these were all strange dead-ends on the great interweb that i have stumbled across; either information that didn't quite line up or information that couldn't be found at all.. That's why i'm asking you guys, the reliable ones, for setting the facts straight and better informing me! ;)

    Ps- i also have some questions regarding calibur comparison and reliable platforms/frames but i'm saving that for after this all gets resolved!! Any idea on CMJ's vs TMJ's? They look to be synonymous from the diagrams i'm seeing but, again, i'd rather hear it from one of you
     
    Last edited: May 26, 2014
  17. JonM

    JonM Moderator

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    sierra and hornady produce total metal jacketed bullets or fmj using a copper jacket not plated. the jacket is swaged into a cup then ran through bullet dies to seal the core inside. its not as cheap or quick as a typical exposed base fmj but it is done for small game hunting for fur bearing animals where expansion and separation of core to jacket while maintaining extreme accuracy are desired.
     
  18. Mercator

    Mercator Active Member

    I can't rermember dealing with CMJ's (or did not pay attention to the corporate-speak) Care to remember who sells them?
     
  19. Secondhand_Hero

    Secondhand_Hero New Member

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    It looks like 'Montana Gold' are the larger sellers but i'm seeing CapTech, Frontier, and a couple of others as well..

    They are using the same 'lead-safe' statements as TMJ's but it maybe the two use different processes on the jackets themselves? i honestly can't tell..
     
    Last edited: May 26, 2014
  20. Mercator

    Mercator Active Member

    No, haven't seen that ammo. Maybe different... but sure quacks like a duck :)