Will 5.56 Cycle thru a 223 cal. Rifle after being run thru 223 Reloading Dies?

[Dee]

I've never actually thought about this but the question is will it? I have A BUNCH of reloaded LC 5.56 military brass loaded with 223 dies. Is the case head different are SHOULDN'T they now cycle thru a 223 Bold Action such as a Remington? Not really interested in what you THINK, but more in what you KNOW on the issue.
 
Thanks, Dan

[Swampman]

I've never actually thought about this but the question is will it? I have A BUNCH of reloaded LC 5.56 military brass loaded with 223 dies. Is the case head different are SHOULDN'T they now cycle thru a 223 Bold Action such as a Remington? Not really interested in what you THINK, but more in what you KNOW on the issue.
 
Thanks, Dan

Yes

[45-70.gov]

http://en.wikipedia.org/wiki/.223_Remington









http://en.wikipedia.org/wiki/5.56%C3%9745mm_NATO

[Old Syko]

45-70's post pretty much covers it.  Aside from that I know for a FACT they cycle perfectly through an Interarms MK10, 700 ADL remington, Ruger 77 and a pair of Sakos.  However ammo loaded for my bolt guns cannot be used in my ARs because they are loaded too long to go into a magazine.

[Dee]

I know I have done this, but it's been years. I read some threads on other websites, and guys were sayin guns like the Remington Tactical in 223, would not chamber 5.56. They didn't mention whether reloading 5.56 in 223 dies changed the INSIDE diameter too much. I have personally full length resized military 3006 down to 2506, trimmed the necks and had excellent results. SO! I figured one could do the same with 5.56 to 223, but it never hurts to ask.

[Lloyd Smale]

ive shot surplus 556 in 223 bolt guns and have used my reloads using standard dies in bolt guns. Maybe those saying it dont work have custom rifles with real tight chambers or most likely are just passing on what someone else told them on the internet. they fit in any factory bolt gun ive tried them in. Anymore though i load all my 223 with small base dies to insure they function in everything but thats more due to wanting reliablility in the ars then it is to function in a bolt gun. In all my many many thosands of 223 ammo ive never once turned a neck on any brass. What i do do is like i said small base size it and i also trim overall lenght each loading as brass tends to grow fast in an ar.

[Swampman]

IMO there's no real difference.  I've used them interchangeably for years.

[Dave in WV]

IIRC the 5.56 chamber has a longer throat and the chamber in the neck area has a slightly larger diameter that allows for thicker mil spec brass.

[Dee]

THAT'S What I was lookin for. I case trim to 223 lengths, so length is not a problem. Case neck area is what I was askin.

[LanceR]

Reloading 5.56x39 NATO brass for use in a .223 Remington chamber is not generally an issue but it is good to keep in mind the usual recommendation to back of the normal starting load by a grain or two due to the smaller case capacity of the NATO case. 

The only other safety issue relating to interchanging .223 and 5.56 ammo doesn't count here and that is the extra 7,000 PSI pressure of the 5.56 cartridge over the .223.  You can fire .223 ammo safely in any rifle made for the 5.66mm cartridge but there are cases where the additional pressure of the 5.56 load is not necessarily safe in a .223 chamber.  For example, a friend has a quite small barrel diameter on a light sporter .223 rifle that predates the ready availability of 5.56mm ammo and due to the small barrel diameter that rifle would not be a good candidate for 5.56mm ammo as the pressure is almost 20% higher than the designed max of the rifle.

Lance

[Dee]

It's the same as loading 3006 with military casings, or as I had said, resizing military cases to 2506.

[Swampman]

IIRC the 5.56 chamber has a longer throat and the chamber in the neck area has a slightly larger diameter that allows for thicker mil spec brass.

but the external cartridge dimensions are the same so it really doesn't matter.

[Dave in WV]

If using military brass in a tight .223 chamber you may need to inside neck ream the brass.

[Bugflipper]

I've never loaded commercial 223 brass for a 223. Just ream out your primer pockets and reduce the load a little for the reduced case capacity and all is well. I fully form the first time. Then neck size only to my tightest chamber and use them in all of the 223 rifles. I don't have to trim them as often as folks suggest they do so guessing the harder surplus cases hold up better than commercial brass?

[Dee]

Your the guy I was lookin for Bugflipper. I did the same thing with 7.65, and 06. Thanks,

[Swampman]

I use the RCBS X-Die....no trimming....