6mmBR vs 223 to 600?

[mattri]

This topic comes up from time to time, usually from someone with a 223 debating whether or not they should re-barrel to 6mmBR. This is a similar question with a bit of a twist.

The 6mmBR is an amazingly accurate cartridge, there is no doubting that. The 223 is no slouch either.

Shooting from the bench, prone, and various field positions- if you had to make a case for the .223 what would it be? For the 6mmBR?

Recoil is minimal in either. The 6mmbr will have the "inherent accuracy" advantage- by how much?

Presume a skilled shooter using comparable rifles/loads/optics etc under similar conditions- shooting once with the 6mmBR and then again with the 223 @ 600- what will the difference be?

 

[mattri]

Really? So .25 vs .30 from one or the other is a constant that is not influenced by a particular barrel, load, day on the line? You're saying that you can shoot better than that difference day in and day out? Not arguing whether or not it can be done, hoping to hear from those that can so that they can chime in with definitive pros/cons.

 

[6BRinNZ]

arguably not much (when the question is asked this way) - but the 6br is very easy to load for and a 1-8 twist is versatile. The 6br is probably a little more tolerant (IMO it is) and you can argue things like shooting the 105 A-max will suffice for target and varminting.

 

[mattri]

Well said, thanks. Maybe a better question would have been: "6mmBR better than a 223 to 600- by how much?" That way people could argue targets, group sizes- the actual measured difference between the two instead of just "x is better than y".

 

[6BRinNZ]

Maybe - .223 is a good round and can be very accurate. I think time is the greatest cost with shooting so I look at cartridges that are tolerant, have a long life, great accuracy, and importantly how easy is it to maintain that level of accuracy. If it can be achieved with fundamental reloading steps and good components then tick. For me the 6br fits the bill.

On any given day with your criteria I would probably back the shooter - but that ignores the level of preparation needed to make a match out of it....I think this is where the question is.

If its a comparison of group size agg then 6br.

 

[6xcshooter]

if you want to compare apples to apples , consider the 22br against the .223. the 22br would be the choice between the two.

 

[jonbearman]

I shoot both and the 6 br comes out the winner over the .223 everytime and I have done side by side in wind to see what the winner was and the 6br is champion with the heavies and the lighter bullets.No doubt you can shoot 90 grainers and make your claims but the 6br or 6 ppc will do better on target everytime.IMHO!

 

[fdshuster]

In our local Hunter and Varmint for score match's from 100 yards to 500 meters I cannot remember ever seeing a 223 chambering competing in the custom class. Short range is dominated by the 6ppc's and 30BR's. For the longer distances fast twist 6BR's and a few others like the 6.5x47Lapua's.

For that matter seldom in the factory class either. The majority of those rifles are Savage's chambered with a fast twist barrel in 6BR.

Basically speaking, 6mm's dominate.

If in doubt enter a competition match and go up against the dedicated benchrest cartridges and see the results first hand.

 

[22BRGUY]

I think if we look at the original intended purpose between these 2 cartridges, it becomes more clear. The .223 was originally designed and intended for mostly combat in AR style rifles and the case was designed to feed well in those semi auto/auto firearms. That is not to say they are not also very accurate, but that was only one of the considerations in it's design.
The 6br on the other hand was originally designed for accuracy and consistency as the most important goal and as was already said, the heavy .224 projectiles are very good but can not consistently outperform the 105 class of .243's.
JMHO

 

[stool]

lol...tell that to the 222....
but i still agree 6br is the better choice

I think if we look at the original intended purpose between these 2 cartridges, it becomes more clear. The .223 was originally designed and intended for mostly combat in AR style rifles and the case was designed to feed well in those semi auto/auto firearms. That is not to say they are not also very accurate, but that was only one of the considerations in it's design.
The 6br on the other hand was originally designed for accuracy and consistency as the most important goal and as was already said, the heavy .224 projectiles are very good but can not consistently outperform the 105 class of .243's.
JMHO

 

[savagedasher]

It is not just a barrel change that must be done changing from a 223 to a 6BR the bolt face is different. To 200 yd a 223 is very accurate from there on 6 MM BR out classes a 223.
Larry

 

[CatShooter]

I think if we look at the original intended purpose between these 2 cartridges, it becomes more clear. The .223 was originally designed and intended for mostly combat in AR style rifles and the case was designed to feed well in those semi auto/auto firearms. That is not to say they are not also very accurate, but that was only one of the considerations in it's design.

That is not true. The 223 was a compromise, and the design is the same as the 222 and 222 Magnum, neither was designed to feed in anything but a 722/700 action. The rifle picked during the qualifying test needed more power than the 222 and had a magazine well too short for the 222 Magnum, and the 223 was born - there is also something to be said for the military not wanting to except a civilian cartridge "off the rack".

Other than lengths, there is no difference in "design" between the 223, and it's two parent cartridges.

 

[mattri]

Interesting replies, thanks.

 

[varmintshooter]

First post here so I might as well start by stirring the pot. With both 6br and 223 shooting 75 grain bullets ( 6br v-max and 223 a-max ) the trajectory would be very close but the 223 would do better in the wind. And yes I do realize that the 6br is more accurate if shooting known distance and wind. For what I do I like the 223 because I get brass for free, use less powder, cheap bullets, cheap dies and still have good barrel life. If money is not an issue and I was competing at 600 yds with flags and shooting sighters I would grab the 6 br.

I have been lurking here for quite sometime and would like to say thanks to everyone for the privilege. Great site.

 

[wapiti25]

For field shooting at ranges up to 400 yds I would go with the 223. You don't sweat the brass that you drop, it is not Lapua. I'm having fun shooting a 223 at 600 F-class matches.

 

[WyleWD]

In our local Hunter and Varmint for score match's from 100 yards to 500 meters I cannot remember ever seeing a 223 chambering competing in the custom class. Short range is dominated by the 6ppc's and 30BR's. For the longer distances fast twist 6BR's and a few others like the 6.5x47Lapua's.

For that matter seldom in the factory class either. The majority of those rifles are Savage's chambered with a fast twist barrel in 6BR.

Basically speaking, 6mm's dominate.

If in doubt enter a competition match and go up against the dedicated benchrest cartridges and see the results first hand.

+1 on Frank's post. Additionally, on any given day it helps to be able to see your bullet holes or point of impact..... and it is difficult on some days to see 6mm holes, let alone 22cal holes or impact. JMHO. WD

 

[Nomad47]

First post here so I might as well start by stirring the pot. With both 6br and 223 shooting 75 grain bullets ( 6br v-max and 223 a-max ) the trajectory would be very close but the 223 would do better in the wind. And yes I do realize that the 6br is more accurate if shooting known distance and wind. For what I do I like the 223 because I get brass for free, use less powder, cheap bullets, cheap dies and still have good barrel life. If money is not an issue and I was competing at 600 yds with flags and shooting sighters I would grab the 6 br.

I have been lurking here for quite sometime and would like to say thanks to everyone for the privilege. Great site.

Varmintshooter, I think it would be a much fairer comparison if you used bullets of equal BC instead of equal weight.

 

[Phil3]

Due to gun range limitations, I only get to shoot at 100 and 200 yards, and have a 223 in bolt and AR configurations. But, I am building a 6mmBR single shot on a Savage target action for those same ranges. Why? Because the 6mmBR simply IS inherently more accurate. I asked this question here once before and the answer was almost universal...the 6mmBR. How much more so for my two guns, who knows, and there may be little difference at these short ranges. But, if I was a betting guy, I would go with the 6mmBR every time. Also, there is a ton of info on this site regarding the 6mmBR which should me help reach peak accuracy. Lastly, I wanted something different. With a 1:8 twist barrel, I can shoot the gun pretty far, if I ever have the opportunity, and I might. On top of that, the 6mmBR uses about 20% more powder than a 223 (not that much of an additional cost), has minimal recoil, and can use the same small rifle primers of the 223. Besides, I think the round just looks cool. Not something you see every day at my range!

Phil

 

[bheadboy]

fwiw, actually the 223 was designed because the 222m case was too straight to feed properly and consistently, thus the taper of the 223, also the idea of possibly heavier fmj mil bullets causing consideration of a shorter case.
however the main reason for the redesign was the taper to insure feed from mag in an auto.
Bob

 

[CatShooter]

fwiw, actually the 223 was designed because the 222m case was too straight to feed properly and consistently, thus the taper of the 223, also the idea of possibly heavier fmj mil bullets causing consideration of a shorter case.
however the main reason for the redesign was the taper to insure feed from mag in an auto.
Bob

Nope... If you bother to look at the chamber and case diagrams of the 223 and it's predecessors, you will find that, within 2 or 3 thousandths of body diameter, they are the same.

There is no more taper in the 223 than the others.