5.56 vs .223

jvbutter

Messages
470
Reactions
96
I have seen some people post 5.56 and .223 as the same ammunition. And I assuemd so. However i have heard that the NATO 5.56 is not the same and more powerful... is this true??? Whats the difference in them?? Will any 223 shoot the 5.56???
 
Messages
58
Reactions
7
I have seen some people post 5.56 and .223 as the same ammunition. And I assuemd so. However i have heard that the NATO 5.56 is not the same and more powerful... is this true??? Whats the difference in them?? Will any 223 shoot the 5.56???
This should help....

<broken link removed>

and some more reasonable info here....

http://en.wikipedia.org/wiki/5.56x45mm_NATO

and a bit more here....

http://ar15barrels.com/data/223vs556.pdf

And there is a bunch more of both good and bad information available on the net....
 
OP
J

jvbutter

Messages
470
Reactions
96
thx much... clears it up... pretty close to being similar.. newer guns are modified to handle it, but check with manufacture first to ensure. oh and seems the cases on NATO rounds are thicker, less powder. Amongst other differences in size
 
Messages
4,017
Reactions
2,637
NATO ammo is loaded about 15,000PSI hotter than SAAMI, when we're talking 5.56 v. .223... you can probably get away with shooting 5.56 ammo in just about any .223, but why put all that extra stress on your chamber? it'll just burn it out that much faster, if nothing else.

with ARs, it can make an even bigger difference.. but that's a whole topic by itself.
 
Messages
2,405
Reactions
554
NATO ammo is loaded about 15,000PSI hotter than SAAMI, when we're talking 5.56 v. .223... you can probably get away with shooting 5.56 ammo in just about any .223, but why put all that extra stress on your chamber? it'll just burn it out that much faster, if nothing else.

with ARs, it can make an even bigger difference.. but that's a whole topic by itself.
One needs to be careful when comparing pressures from published "specs". Pressure measurements can be obtained in a couple of places. One is at the case mouth and another in the "chamber".

A Nato round developing 3250 fps doesn't generate much greater pressure than a "civilian" round traveling the same speed (bullet weights being equal).
The piezoelectric sensors or transducers NATO and SAAMI use to conduct the actual pressure measurements also differ. This difference in measurement method accounts for upwards of 137.9 MPa (20,000 psi) difference in pressure measurements. This means the NATO EPVAT maximum service pressure of 430 MPa (62,366 psi) for 5.56 mm NATO, is reduced by SAAMI to 379.21 MPa (55,000 psi) for .223 Remington.
Basically, the readings are the same, just measured in different places.

The NATO chamber has a longer leade or greater distance from ogive to rifling on a chambered round. This can alter the pressure readings drastically. Just as any handloader adjusts his powder load depending on OAL, and the resulting jump to the rifling, one needs to expect this if shooting a NATO round in an .223 barrel. It can be particularly dangerous in a tight chambered target rifle with little or no freebore or leade. The additional leade allows for more powder to be employed, yielding higher velocities, with lower chamber pressures but can often result in lower accuracy.
 

UPCOMING EVENTS

Cerberus Training Group - Run the Gun Rifle
Cerberus Training Group
47 Cattle Dr, Goldendale, WA 98620, USA
Arms Collectors of SW Washington Gun Show
Battleground Community Center
912 E Main St, Battle Ground, WA 98604, USA
Albany Rifle & Pistol Club (ARPC) Gun Show
Linn County Expo Center
3700 Knox Butte Rd E, Albany, OR 97322, USA

LATEST RESOURCE REVIEWS

  • Copeland Custom Gunworks
    5.00 star(s)
    1911 guru!
    Tim Copeland rebuilt and refreshed an old Colt 1911 Gold Cup for me that needed all new springs, new extractor & replaced a loose ejector. Found...
    • Knute
  • 36 Pit
    4.00 star(s)
    Went here this morning. This was my first time shooting on public land in Oregon. The guys from Trash No Land were there as well as other...
  • HighLine Firearms
    5.00 star(s)
    Good prices, interesting items
    I like taking a drive through farm country to this spot... nice selection.
    • kbf64
  • HighLine Firearms
    5.00 star(s)
    Good Friday!
    Had a great first time visit that included a transfer, a special order, and some trading. Can't wait to come back! Also I realized after I got...
  • HighLine Firearms
    5.00 star(s)
    Upstanding Vendor!
    Have worked with this business twice and both times were outstanding! Will definitely keep going to him when I'm up in that area! Shoot, will...
Top Bottom