Survival

Wednesday, June 27, 2012

5.56 ammo discussion

Let's talk about 5.56 NATO ammunition......

For those of you with AR15's in this common caliber, I would like to pass along my opinions and a few links to aid you in making an ammunition purchase.




First,determine whether your rifle is chambered in 5.56 NATO or 223 Remington.  This should be permanently stamped into the barrel.

What is the difference between the two?

Exterior dimensions on the two rounds are identical, but 5.56 NATO ammo is typically loaded to higher pressures and velocities than the civilian-grade 223 Remington.

The chambers in 5.56 guns are slightly looser, with a little more headspace, and a bit longer throat to provide better operational reliability than a SAAMI spec 223 Remington chamber.

If your gun has a tight 223 Remington match grade chamber and you fire a hot 5.56 NATO round in it you may be creating an unsafe condition.  Make sure you select the right ammo for the rifle.

Once you have determined the particular chambering of your rifle, you need to find out the twist rate of the rifling.  This is also usually stamped on the barrel.  If not, you can insert a cleaning rod with a tight fitting bore brush into the barrel and measure the distance it takes to complete one full turn.

Twist rates have varied greatly over the years, from the earliest AR's having a 1:14 (one twist every 14 inches) to some of the modern guns having a 1:7 twist.  1:12 and 1:9 are also very common.

The reason you need to know this is that the slower twist rates will not stabilize heavier bullets.  For the 1:12 and 1:14 twist guns, you must shoot 55 grain or lighter bullets.  The 1:9 guns can handle 62 grain bullets, and the 1:7 twists will often handle 77 grain projectiles.

If you can pick and choose between otherwise identical rifles in a store, the 1:9 twist barrels tend to provide the best overall rate for a defensive gun used in a survival situation with 55 or 62 grain bullets.

Which brings us back to ammunition.......  Since this is a survival blog, and I assume that readers here are interested in preparing their rifles for a survival-type situation, here are my recommendations for the best ammo for preppers:


  • Choose Mil-Spec 5.56 type ammo (assuming you have a 5.56 chamber).  The difference between this type of ammo and commercial 223 ammo is greater pressure and velocity for better terminal performance, annealed necks on the brass for greater consistency, lacquer sealed primers for moisture resistance during long term storage, and crimped case necks to prevent bullets from being forced back into the case during feeding.  
  • Mil-Spec ammo, in either M193 or M855 versions are usually cheaper to buy in bulk compared to civilian grade ammo.  I cannot overstate the importance of this- you will need to have large quantities of ammo on hand; don't choose some nifty, whiz-bang load designed for a SWAT sniper team- you will never be able to afford to buy it in a large enough quantity at the prices they get for this stuff.
  • I prefer M193 (55 grain @ 3250 FPS) ammunition for its combination of price and performance.  Green tip M855 (62 grain) is popular too, but M193 destabilizes quicker in tissue giving you bigger, better wound channels on torso hits for faster incapacitation.
  • Stay away from 223 Remington soft points.  The vast majority of these were designed as varmint bullets and will nearly explode on impact.  This means, of course, that they do not penetrate very well at all.  The few soft point loads on the market that were not designed for varmints are priced over $1 per round; too expensive to buy in bulk.
  • Stay away from steel cased ammunition.  Quality is not up to par with the Mil-Spec loads, and firing brass cased ammo in your rifle after firing steel cased ammo can cause extraction problems due to the lacquer/polymer coating building up in the chamber.  This is bad Ju-Ju.
  • Plan on buying ammo in 1000 round case quantities to get the best deals.  I recommend having at least 1000 rounds on hand as a minimum.  2000 to 3000 is preferred.  


There are some good, modern open tip match (OTM) bullets on the market that are showing good performance in ballistic gelatin and over in the sandbox, but again, price is prohibitive on this ammo.  Having vast quantities of good ammo outweighs the benefits of a slightly better performing round that you can't afford to stock as many of in a survival situation.

I have done business with the following ammunition dealers, and can recommend them both from a price and customer service prospective.   Of course, they aren't the only outfits around that are good to deal with, but I have had good luck with them.  I am not affiliated with these businesses or any others; buy where you want.

AMMOMAN.com- the price you see includes shipping to your door.  They mostly sell in large (500-1000 round) quantities.

LuckyGunner.com- they sell in both small and large quantities and have reasonable shipping rates.

For those of you who are truly gluttons for 5.56 ammunition information, here is where you need to go for every last detail ever written about ammo for the AR- the AR15.com Ammo Oracle.

Feel free to use the comment block if you have any questions or for further discussion.



LWM out..............




2 comments:

  1. OK, finally got around to logging on and have actually read thru this post. Tks for your perspective regarding 5.56 ammo. Exactly the info I need on this topic.

    ReplyDelete