Comments

1. On February 3, 2020 at 2:09 am, Longbow said:

   Ooooo! Ahhhh!

   People make way more of this than they should.

2. On February 3, 2020 at 3:16 am, Georgiaboy61 said:

   Way too much bandwidth is spent on this issue… so here we go again…

   5.56×45 NATO versus .223 Remington: Much of the different between these two chamberings boils down to three things – the characteristics of the firearms using the ammo, mil-spec versus the sporting/civilian world, and real differences between mil-spec and civilian brass.

   Military issue long arms using 5.56×45 NATO ammunition are typically select-fire, either assault rifles or squad automatic weapons. As such, they – and the ammunition – will be used under harsh conditions. Weapons which are overheated, dirty, fouled with carbon residue, perhaps. Ammunition which may be in pristine, as-issued condition, or perhaps covered with dust or dirt.

   To account for such possible conditions, mil-spec arms have generous chamber and throat dimensions, to assist in positive, reliable feeding, chambering, firing, extraction and ejection. A degree of precision and accuracy are sacrificed in order to strengthen reliability – the foremost virtue of any combat weapon. Match-grade accuracy not being necessary in most combat environments, and fail-safe reliability being just that necessary. That soldier or Marine must know that when he pulls the trigger, his bang-stick must go “bang!” every time…

   Because it may be used under less-than-ideal conditions, mil-spec 5.56×45 NATO brass is thicker, stouter and tougher than civilian .223 brass, which may or may not rise to these standards. Automatic weapons place a lot of stress and strain on the case, which is why NATO-spec M193 or M855 FMJ/Ball` is found in NATO-spec brass 5.56×45 cases.

   Civilian arms marked as “223 Wylde” offer greater accuracy and precision, but at the cost of tighter chamber dimensions, which may not handle all varieties of .224-caliber ammunition, military or civilian in origin. The best bet for most civilian shooter is to get a carbine/rifle marked as being safe for either 5.56 or .223. Unless one is striving for match-grade accuracy, when one of the specialist chamberings is called for.

   Because 5.56×45 NATO brass is made somewhat thicker and heavier than most varieties of .223 Remington cased-ammunition, it is wise for the reloader to back off 1-2 grains on the powder charge, all else being equal, i.e., bullet type/weight; primer, volume/type of propellant used. Or else risk unsafe pressure spikes due to the smaller and thicker-walled case of the NATO brass.

   The thicker, heavier case walls of the NATO-spec case mean that it will extract and eject more-reliably in comparison to its weaker, thinner-walled civilian cousins, who may tear or suffer case head separation upon the violence of extraction and ejection in a self-loading rifle or carbine.

   Also, again because of the stouter construction of the military-spec case, 5.56×45 NATO tends to be loaded to higher pressures and muzzle velocities than its .223 Remington equivalents. But not always, so know the characteristics of the load you are shooting! Some manufacturers load their civilian offerings in brass every bit as stout and durable as their military, NATO-spec offerings. Whereas some skimp on case material and make their civilian .223 Remington cases tough-enough for a single use only. Even a well-constructed case is recommended to be used only 3x in a semi–automatic/self-loading rifle, before being discarded. Typically, a case used in the bolt-action rifles only can withstand 8-10 firings before being used up.

   One last small item: NATO-spec ammunition is supposed to be treated with sealant to render the cartridge water-proof. A small amount of color – typically red or blue-violet – appears over the primer-primer pocket and some will also be visible around the case mouth where the neck grips the bullet. This is the sealant used to water-proof the cartridge. Many civilian manufacturers of 5.56/.223 ammo do not use this step, as a means of making their loads more-affordable to the public. Know before you buy, if this is a necessary feature for your needs.

3. On February 3, 2020 at 9:50 am, Fred said:

   GB61, do you have data or documentation of the differences in wall thickness?

4. On February 3, 2020 at 1:37 pm, MTHead said:

   GB is right in most all he’s saying Fred. But. 5.56 is annealed, (Softened) around the front so that it seals at the neck of the case. Rather than the base. 223 has a pressure standard of 55,000 PSI. And 5.56x45NATO has a pressure standard of 62,350 PSI.
   This pressure increase was the answer to shorter barrel lengths, and the need to maintain bullet speed/ impact cavitation.
   Chambers are generally cut with more or less freebore, (the space between the chamber and where the bullet actually contacts the lands and grooves.), to accommodate those pressure standards. As well as case thickness.
   Also, does anyone truly believe theirs an ammo manufacturer in the world that would hand you two cartridges with identical case demensions. chamber one to the other. But one would blow-up your gun and kill/maim you. And the other would shoot just fine? No, I don’t think so either.

5. On February 3, 2020 at 1:41 pm, Fred said:

   Mr. Harrell seems to indicate that he finda no difference between the casings.

6. On February 3, 2020 at 1:52 pm, Georgiaboy61 said:

   @ Fred

   There have been studies done, but we needn’t resort to that. If you simply weigh a representative sample of new 5.56 and .223 cases from various manufacturers, you can immediately see that some makers of .223 Remington used more material in their cases than others. Some spec-up nicely with 5.56, whereas others do not. In other words, case weight as a surrogate for wall thickness/rigidity.

7. On February 3, 2020 at 2:35 pm, James Harris said:

   .223 tends to use dirtier propellent than 5.56; makes cleaning more arduous.

8. On February 3, 2020 at 2:40 pm, Fred said:

   Ah, I may have drawn the opposite (inverted) conclusion from the vids statement. Thanks.

9. On February 3, 2020 at 3:57 pm, MTHead said:

   I believe you will find the only real difference in the two is the pressure standard. 7,350 PSI is not enough in SAAMI spec. barrels to do anything but give a bunch of ambulance chasers something to litigate with. And give safety personal / lawyers something to feel relevant about at meetings.

10. On February 3, 2020 at 4:42 pm, Longbow said:

    Stop debating how many angels can dance on the head of a pin… and go shoot!

11. On February 3, 2020 at 6:17 pm, Wes said:

    There’s one simple thing that needs to be known about the difference in MV figures on the boxes (and shame on Federal). They didn’t INTEND to say that the 5.56 is slower than AE223. The number they’re using is what the M193 velocity spec is, 3165 – BUT that velocity is to be achieved 78 FEET (25m) from the muzzle of a 20″ barrel. This will usually wash the ACTUAL MV out to something like 3280 or so. In contrast, .223 Rem velocity is done using a SAAMI-spec 24″ barrel, so when shot in a typical AR barrel it will give up velocity to the 5.56. Federal’s mistake is that they should either cite the true MV on the 5.56, or mention that it’s from a 20″ barrel measured 25m away. Either would be correct, however either would cost them some extra $$ to change what they’re doing now.

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