Bolt action .223/5.56 question

Blade37db

New member
I've been researching bolt action .223/5.56 rifles (Remington 700, CZ 527, Steyr Scout, Ruger M77) and have a few questions:

Can you shoot 5.56 in a .223 bolt action rifle? I know you can't in a semi-auto (AR, Mini), but there seems to be some debate on bolt-actions.

Why are some bolt action .223 barrels in 1:12 twist when semis are usually 1:9 to 1:7? Would the 1:12 prevent you from shooting heavier weight ammo (75 & 77 gr)?
 
It is not recommended due to higher chamber pressures that can be generated with the 5.56, but I have shot them in about every 223 bolt gun I have had. This includes: My model 70 XTR, Savage 110, Remington 700 BDL, and VLS, and last but certainly not least my Remington 788. I didn't have any issues like stuck bolts, blown primers, or case head separation. I don't make a habit of using them, cause I prefer my finer handloads, and I don't want to stress the gun anymore than I have to, but I do not fear shooting them.
 
Would the 1:12 prevent you from shooting heavier weight ammo (75 & 77 gr)?

yes... most were made for bullets in the 55 grain range... personally I'd look for a 1 in 9 twist if you were wanting to shoot heavier bullets
 
Can you shoot 5.56 in a .223 bolt action rifle? I know you can't in a semi-auto (AR, Mini), but there seems to be some debate on bolt-actions.

Why are some bolt action .223 barrels in 1:12 twist when semis are usually 1:9 to 1:7? Would the 1:12 prevent you from shooting heavier weight ammo (75 & 77 gr)?

1) The same rules still apply. If your rifle is chambered for .223 Rem, it is ill-advised to fire 5.56 NATO ammunition through it. They operate at slightly higher pressures due to the slightly tighter .223 chamber and may cause an overpressure (but it typically won't do any significant amount of damage to the rifle).

2) Many bolt guns have 1:12" twist because most bolt action .223 rifles are used for varmint hunting. That means that the heaviest round used is typically around 55 gr, with the majority of the v-max rounds being in the 40-45 gr range. Would it prevent you from shooting 75-77 gr ammo? Pretty much, yes. The slower twist will not be able to stabilize the heavier stuff.

ARs have faster twists so that they can handle heavier rounds such as tracers and M855s.
 
Well, my point is I don't see any reason to worry about using the 5.56 stuff in a bolt gun. They are mostly modified mauser actions which are the strongest actions there are except for the 788. Stronger than any auto loader. The leede is longer in 5.56 than it is in 223. My favorite handload is made with military brass. I just can't duplicate it with 223 rem brass. I have successfully stabilized heavy bullets with my 1 in 12 twist rifles. It was about 7 yrs ago, so I don't remember the exact grain, but somewhere around 70. I think I grouped about 1.25" at 100 yrds.
 
Of course if you got an bolt gun in 223 made before the Internet came about, the 5.56 would work great.

We never had problems until the Internet told us we couldn't do it.

Or you could ask some one to provide legit proof of a case a problem occurred. Good luck on that one, I've been looking for several years and haven't found any.

Back about 1978 I got a Rem 700 BDL Varmint to use in LE Sniping. To be on the safe side (liability wise) the dept agreed it best to use FMJ M193.

That's all I shot in the gun until I retired from both LE and the NG and didn't have access to M193 and went to reloads.
 
The 2 are interchageable in all rifles, bolt or semi. 5.56 may be loaded to slightly different specs, but if you buy ANY ammo in ANY chambering you will find ammo loaded to different specs. Federal 30-06 ammo may be a little hotter and may have slightly different case measurements than Remington ammo. We don't have 2 different names for 30-06. The chamber dimensions on a Savage rifle could be quite different from a Winchester even though both are stamped 30-06, or whatever.

You might in some very rare cases find some 5.56/223 ammo that may be unreliable in some rifles regardless of whether they are stamped 5.56 or 223. But the same could be said of any other chambering.
 
"Can you shoot 5.56 in a .223 bolt action rifle? I know you can't in a semi-auto (AR, Mini), but there seems to be some debate on bolt-actions."

Typo? You certainly can shoot 5.56 NATO in an AR; that's generally what they are chambered for. SAAMI sets specs for sporting rifles, and since military ammo (5.56 NATO) is not made to SAAMI specs, it doesn't have their "blessing". Obviously, a lot of folks shoot it without a problem. My Sierra manual has separate sections for AR and bolt action, but the powder charges are actually a little higher for the same bullet in the bolt action section.
 
Not a typo ligonierbill. Even if it's an AR, if it is marked .223 (not 5.56), I didn't think you could shoot 5.56 in it.
 
AR loads usually have a heavier bullet so the twist is 1:9 and so on. The bolt action .223 was intended for varmint hunting where you only need a 40-55gr bullet so the twist does not have to be as fast to stabilize the smaller bullet.
 
That has to do with bullet stability, not whether one can shoot 223 vs 5.56 or not.

I have two ARs, one a SP1, with a 1:12, one a White Oak Service Rifle, 1:7.

I also have two Bolt guns, both Rem 700s, one with a 1:12, and one with a 1:7.

Either shoot 5.56 or 223s quite well assuming you match the bullet weight to the twist.

The exception being the 1:7s will pretty much shoot any weight bullet except for the thin jacketed bulles designed for the Hornet.
 
Why are some bolt action .223 barrels in 1:12 twist when semis are usually 1:9 to 1:7?

The CZ 527 is a 1:9 twist. That provides pretty wide coverage across a pretty wide range of bullet weights.
My CZ 527 with the factory HS Precision Kevlar stock shoots loads from 40 grains to 63 grains very accurately if I load to the right velocity and seating depth. My best 25 hand loads average 0.388 for 222 measured groups.
It's best 10 hand loads include one 63 grain load and average 0.339 for 73 measured groups.

Would the 1:12 prevent you from shooting heavier weight ammo (75 & 77 gr)?

The 1:12 twist was designed for lighter bullets and favors bullet weights up to about 55 grains. An individual rifle will shoot heavier bullets even with a slow twist, but they probably won't be as accurate.
My CZ 527 shoots 69 grain bullets pretty well with three different loads under 0.5 inches on average. It has even shot 77 grain bullet loads on average under 0.6 inches.
As you can see, it has a pretty wide range but the accuracy drops off.

My son's 1:8 twist AR likes 60 and 63 grain bullets best when measured for accuracy. It will shoot 55 grain bullets well but not quite as well.

The 1:7 twist was designed for heavy bullets in the 69 to 80 grain range primarily to increase the kinetic energy at the target and gain more hitting power. Most 1:7 twist barrels won't shoot the lighter bullets very accurately, but there are exceptions.

My experience with a 1:7 twist is that the accuracy was about twice as good with the 77 grain bullets versus the 55 grain bullets.
Of course, every rifle and barrel is different, so the details only apply for the rifles I am familiar with, but the general rules seem to hold.
 
Most 1:7 twist barrels won't shoot the lighter bullets very accurately, but there are exceptions.

That's not quite true. The Army use the Mann Accuracy Device (1:7) to test their ammo. They use the 52 gr Sierra to test the Mann, it shoots the 52s right around .18-.19 groups.

First picture is my Mann Device: It shoots everything from the 52 grn match bullets to the 90 grn Bergers.

Second is from the Army Manuel regarding 1:12-1:7 and different weight bullets showing the 1:7 will shoot both, the 1:12 wont.

Mann%20in%20stock.JPG


Twist%20compairson.jpg
 
I don't think it is a good idea to make generalizations about all rifles and all ammo based on one set of data and one specialized testing device.

I don't question that the Mann device would shoot 52 grains accurately even if it was a 1:7 twist, especially if it was shot in a fixture.

Interestingly, it doesn't look like an AR, more like a single shot.
My data on 1:7 and 1:8 twist ARs says that they didn't shoot 55 grain bullets as well as 77 grains in the 1:7 and 60 and 63 grains in the 1:8. Both shot the 52 grains worse. That is what my data says.

As I posted, the comments I made still applies to my measurements since they were shot through rifles I had my hand on and were shot over bipods and rear bags, not from fixtures.

I didn't say that the 1:7 rifles wouldn't shoot both light and heavy rounds, just that they didn't shoot the lighter rounds as accurately. I would agree the the chances that a 1:12 twist would stabilize the heavier bullets are pretty low but I presume that it might be possible in some rifles based on what I read in this forum.

All I can vouch for is my data and I wasn't making generalizations about special rifle test devices and any other rifles.
However, the general trends for about 6 rifles indicate that my comments might at least be reasonable for some other rifles as well.
 
Interestingly, it doesn't look like an AR, more like a single shot.

It isn't the platform that is being tested, it is the barrel twist. A 1:9 twist AR barrel will be no different than a 1:9 twist single shot barrel. By that I mean, 1:9 is 1:9, it does not vary because it is in one platform or another.


My data on 1:7 and 1:8 twist ARs says that they didn't shoot 55 grain bullets as well as 77 grains in the 1:7 and 60 and 63 grains in the 1:8.

My 1:8 twist AR shoots 55 gr just fine. I shot a 3-Gun match yesterday and was hitting 500 yard targets on the first shot every time. The same can be said for 3 of my teammates who were also shooting 1:8 twist ARs with 55 gr rounds. The 1:7 and 1:8 will shoot bullets from 55-77 gr just fine, and will shoot the heavier rounds better than a 1:9 twist.

But you are right, some guns are different than others. However, it is much more likely that you will find a 1:9 twist AR that likes heavier bullets than a 1:7 or a 1:8 that doesn't like 55 gr projectiles.
 
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