Have read that Mini-14 in 223 should not use 556 ball ammo as there is a size difference in the cartridges.

Does that also hold true in a bolt action rifle?

I am not an expert, but I won't shoot 556 in anything not labelled for 556.

Simple.

I don't know about size differences, but 5.56 can be loaded to slightly higher pressures than .223, so it is not cecessarily safe to go in that direction. But .223 in a 5.56 gun is safe.

There are countless Internet articles and discussions about the differences between the 223 Remington and 5.56mm NATO, but this this is a good one that covers the subject in technical detail, including the fact that actual maximum chamber pressures are very similar. The main differences between the two cartridges are chamber/barrel leades and bullet design/shapes. Shooting any cartridge whose bullet contacts the barrel rifling before firing can raise chamber pressures very significantly, and because the 223 leade is typically shorter than that of 5.56 barrels, that’s a possibility.

In following this question off and on for several years I have formed my own opinion about theory versus reality. There are so many types of 5.56 ammunition and so many rifles chambered for 223 that I must believe that not all shooters who own both are aware of the warnings about shooting the former in the latter. In view of that fact and without suggesting that anyone ignore SAAMI or manufacturers’ advice, it seems to me that if there was a serious danger in the practice, we’d hear of guns blowing up all the time. But we don’t.
I fire various types of 5.56 ammunition in my 223 bolt action rifle without ever having seen any excessive pressure signs such as difficult extraction, flattened primers, etc.

My experiences are, however, limited to a few types of ammunition, so if I tried something else that could change. The best thing is to avoid tempting fate. Rather than buying 5.56 type ammunition for training and practice, I just purchase Federal AE223 which is a 223-spec load that works fine in my ARs and my other guns.

I've shot a ton of M193 ball, (mostly LC) thru my Mini 14 back in the day,
no issues
no drama
no damage to the gun or me

I picked up a bolt action 223 savage with scope combo for $200 after rebates. After I brought it home I realized I have a 556 ammo, not .223. I did some searching on the issue and it comes down to pressing your luck. Firing one 556 from a 223 may have no noticeable effects, repeatedly doing just might.

quote:

Originally posted by gpbst3:
Firing one 556 from a 223 may have no noticeable effects, repeatedly doing just might.

If one or a few shots have no noticeable effects, i.e., indications of high pressure, what could firing more shots do?

If rifles are fired with ammunition at safe chamber pressure levels, the rifling will wear out sooner or later, but the barrels don’t just fail and blow up one day unless there is something seriously wrong with them. If that wasn’t true, any barrel might blow up unexpectedly regardless of the ammunition fired in it.

quote:

Originally posted by abnmacv:
Have read that Mini-14 in 223 should not use 556 ball ammo as there is a size difference in the cartridges.

Does that also hold true in a bolt action rifle?

I thought most Mini-14s were chambered in 5.56 (not .223 Remy). If so, then there should be no 556/223 issues.

The article sigfreund references is a good read.

In an AR-15, I can see wanting to use 556 ball instead of 223 FMJ, as the 556 is generally loaded to a higher muzzle velocity. Given 55 grain FMJ need for velocity to fragment, the additional velocity helps increase the bullet's effective range.

But I can't see wanting to use 556 ball ammo in a 223 bolt action rifle -- or in a precision 223 AR-15. From what I've seen, 223 bolt actions are generally made with accuracy in mind -- 556 ball is inherently an inaccurate load. Furthermore, in my 556 and 223 chambered rifles, 556 match/varmint ammo is never as accurate as its 223 counterpart. Sure, the 556 versions have more muzzle velocity, but that MV serves no purpose if accuracy goes south.

I have lost count of the number of years that it's been since I purchased or shot any 556 ammo.

If it's not stamped on the firearm, I'd suggest not using it. My son just bought a Mini-14, and it is clearly marked 5.56. But I know they make .223 models that aren't.

It's similar to shooting +P out of a non +P rated firearm. You may not have any issues, or you might. Why chance it?

5.56 generate higher chamber pressures, but the leade is the main concern.

The mini 14 is capable of shooting any 223 or 556 ammunition inaccurately.

quote:

Originally posted by abnmacv:
Have read that Mini-14 in 223 should not use 556 ball ammo as there is a size difference in the cartridges.

Does that also hold true in a bolt action rifle?

When it comes to the Mini-14, here is Ruger's official position on the issue, which is at their website's FAQ.

"With the exception of the Mini-14® Target Rifle, which accepts only .223 Rem. ammunition, .223 Rem. and 5.56 NATO can be used in all Mini-14® rifles and Ranch Rifles.
Please note that "Military Surplus" 5.56mm NATO can vary greatly in its quality and consistency."

As for bolt rifles, I do not believe that any recent vintage (20years and never) .223 bolt rifle would be inconvenienced shooting 5.56 ammo, since it so prevalent. The difference is load is inconsequential in a modern bolt.

The leade issue is the only one of concern and it's easy to check. Use a marker to paint the bullet black and then in a safe location, chamber the round and pull it out again. If you feel any resistance when you're closing the bolt, stop right there, open the bolt and take out the round; it's touching the lands. If you do close the bolt completely, open it and remove the cartridge. Inspect the bullet, if it has any markings on it, it's touching the lands and that's an issue, don't fire that ammo in that rifle.

quote:

Originally posted by car541:
The mini 14 is capable of shooting any 223 or 556 ammunition inaccurately.

Doh!

quote:

- 556 ball is inherently an inaccurate load.

This is not all that accurate..you have to remember that the gun 5.56 is made for has a mil spec of putting a round into 4MOA at 100 meters, so it may be that the rifle barrels (throats and muzzle end)may be trashed compared to what we normally use ammo to do, but still fall w/I the .mil requirement.

I have fired ball ammo from my bolt gun and have no problem keeping it in the bull at 100, and I use handloads and get much better results in the same gun at the same distance...but the ball ammo does what it is supposed to do and isn’t inherently inaccurate.

quote:

Originally posted by fritz:

quote:

Originally posted by car541:
The mini 14 is capable of shooting any 223 or 556 ammunition inaccurately.

Doh!

Yeah, but we enjoy wasting ammo much more than in an AR or AK. It's just a fun gun to shoot.

Thanks for the info.

I've shot a boatload of 5.56 in various 223 bolt action rifles with zero problems. We used to do it as a source for cheap reloading brass.

quote:

Originally posted by MikeinNC:

quote:

- 556 ball is inherently an inaccurate load.

This is not all that accurate..you have to remember that the gun 5.56 is made for has a mil spec of putting a round into 4MOA at 100 meters, so it may be that the rifle barrels (throats and muzzle end)may be trashed compared to what we normally use ammo to do, but still fall w/I the .mil requirement.

I have fired ball ammo from my bolt gun and have no problem keeping it in the bull at 100, and I use handloads and get much better results in the same gun at the same distance...but the ball ammo does what it is supposed to do and isn’t inherently inaccurate.

This boils down to our individual definitions of "accurate".

All of my AR-15 uppers shoot a variety of factory match and varmint loads well. The barrels range from 14.5" to 24" in length, with 5.56 and .223 chambers, with twists of 1/9 to 1/7. Even my most picky barrels have multiple ammo types that shoot under 1 MOA. And I don't mean just 5 rounds at 100 yards, but holding vertical under 1 MOA out to 500 yards, and beyond. Every barrel I've owned has shot 1/2" to 3/4" groups at 100 yards with their accuracy loads. My best barrels have some .3" to .4" groups -- when the stars are aligned.

American Eagle 55 FMJ has been the most consistent ball ammo in my ARs. It's effectively a 2 to 2.5 MOA load in my rifles. Occasionally a 1.5 MOA group arises at 100 yards, but they seem to be offset by the 3 MOA groups. I've shot some the cheapie FMJ loads -- like Wolf and Brown Bear -- and their accuracy is worse than AE 223.

That's inaccurate ammo in my book. As for the mil spec of 4 MOA -- that is completely unacceptable to me in any rifle I'm behind. If that's good enough for the mil spec, so be it. But it's not good enough for me.

quote:

Originally posted by sigfreund:
There are countless Internet articles and discussions about the differences between the 223 Remington and 5.56mm NATO, but this this is a good one that covers the subject in technical detail, including the fact that actual maximum chamber pressures are very similar. The main differences between the two cartridges are chamber/barrel leades and bullet design/shapes. Shooting any cartridge whose bullet contacts the barrel rifling before firing can raise chamber pressures very significantly, and because the 223 leade is typically shorter than that of 5.56 barrels, that’s a possibility.

This is what I've followed as well. Not sayin' the gun will blow up, but SAMMI sez less safe. I've had hard extraction, and seen blown primer pockets scorch the bolt face.

There is a second issue of some 556 is 62 grain or heavier. In a .223 bolt gun with slow twist rate this is also has resulted in off the paper poor accuracy as the bullet shape and weight is not properly stabilized. Why waste your range time shooting poorly.

quote:

Originally posted by preten2b:
In a .223 bolt gun with slow twist rate this is also has resulted in off the paper poor accuracy as the bullet shape and weight is not properly stabilized.

Something to keep in mind.

When I decided to get a 223 bolt action, I settled on a Tikka T3 Tactical to match the same rifle I had in 308. At the time the factory web site said that it was available with 1/12" rifling or 1/8". I obviously wanted the second for use with heavier bullet loads, but when I tried to find one, I was told by Beretta that the ones being imported then had 1/10" barrels, and that sent me on a quest for an older 1/8. I finally found a dealer who tracked down a new/old stock, but I could only guess that everyone expects us all to shoot long, heavy bullets in ARs, but not in bolt guns.

Years ago my cousin bought a Savage 223 bolt rifle and I believe he had the chamber altered in order to fire 5.56 through it. I'll have to check with him to get the particulars but it must have been cheap enough to be worth doing.