.223/5.56 question

[Lennyjoe]

Im tooling up to start reloading and happened upon about 800 rounds of 5.56 brass and have a question.

Im assuming that since there are no 5.56 dies out there then its safe to use .223 dies. Gonna be shooting it out of an Oly Arms 5.56 Ultra Match Barrel.

Is this a correct assumption?

My plans are to reload 10MM, 45 ACP and .223 in the Lee Turret press and 30-06 and 270 in the single stage press.

Got just about everything but a tumbler, powder and bullets.

Im almost there........

 

[Otherguy Overby]

223/556

I've not started reloading 223 yet.

The chambers are slightly different.

IOW, it's safe to shoot .223 in a NATO chamber, but there's a chance of overpressure when shooting 5.56 in a .223 chamber.

So, if you want the best accuracy, and reload, shoot .223 out of a .223 chambered rifle.

If you want to shoot milsurp 5.56, get a similar *5.56)chambered rifle.

I've both on my list.

BTW, an Oly rifle is probably a .223 chamber. The information about this is on their website.

 

[Dave R]

Speer No. 13 reloading manual says you can use .223 dies for 5.56. The loads they list were all developed using mil-spec brass.

 

[Lennyjoe]

an Oly rifle is probably a .223 chamber

Barrel is stamped 5.56 UM

 

[Otherguy Overby]

Sometimes when you read something, you remember it somewhat differently later...

From Olympic's website in their ammunitioin faq:

Olympic chambers specifically are cut to 5.56 NATO specs via Clymer reamers in all button rifled barrels, and minimum SAAMI spec .223 Remington on all SUM Ultramatch barrels. Our rifles will provide superior accuracy, partly based on that fact.

Anyway, the second is what you wanna avoid shooting milsurp ammo in.


for a bit more, from Fulton Armory: (http://www.fulton-armory.com/556-vs-223-Chambers.htm )

If we are talking about .223 Remington SAAMI-spec chambers in an AR15, OH NO!

Do NOT use such a chambering if you EVER plan on shooting any military NATO 5.56 ammo, which happens to be only the most common, least expensive and most widely used AR15 cartridge available in all the world. In other words, NEVER buy/use a SAAMI-spec chamber in a battle rifle, especially if the barrel and chamber are chromed, as you cannot fix it!

Here's the problem. Many NATO cartridges have bullets that will become jammed into the rifling of a SAAMI chambering (the throat is too short). This is VERY DANGEROUS, for a great number of reasons.

Fulton Armory uses a "5.56 Match" chambering in its rifles/uppers/barrels (in fact our barrels are marked as such), which is a slightly modified SAAMI chamber with a tad longer throat to accommodate NATO bullets. The Fulton Armory 5.56 Match chamber allows for the safe and reliable use of all SAAMI and NATO ammo, while offering the accuracy potential of the SAAMI chamberings with match commercial cartridges. Remember, there's often a large difference between bolt guns and military rifles. This particularly true for the 5.56 vs .223; Fulton Armory is well known for the finest performance for any given platform, and our 5.56 Match chamber is one way we achieve that performance with the AR-15-type rifle.

Hope this helps.

Best regards,

Clint McKee

Does any of the above help? You could call Olympic Arms and ask which chamber you have. A google search on: .223 v 5.56 nets lots of info.

 

[Lennyjoe]

I checked today. Its a 5.56 SUM barrel.

 

[Otherguy Overby]

I checked today. Its a 5.56 SUM barrel.

Olympic....

Chamber Type: SAAMI on all rifles prior to June 2001, after June 2001 all chrome moly barrels will be done with an M16 type chamber, and the Stainless Ultramatch will keep the SAAMI chamber. (unless other is specified, barrel is always marked 5.56 no matter what the chamber is)


I ran across the above while looking for something else. Now ya got yer answer, I hope...