Which AR to buy?

[Alex45ACP]

I'm looking to buy an AR15 and have questions.

What's the difference between 5.56 & .223? I think I remember reading that 5.56 can take .223 but not the other way around, is that right?

What's the difference between an "izzy" flash suppressor and a "birdcage" flash suppressor?

What are twist rates? I think I read on another site that 1:9 means the bullet spins 9 times in 1 inch of the barrel, (or maybe it was 1 time in 9 inches ). What are the advantages and disadvantages of different twist rates?

Any brands or models you prefer? My friend has 2 Bushmasters he's very happy with so I might go with that brand.

And finally I know I'm opening up a can of worms here but... is the AR15s reputation for unreliability accurate?

 

[browningguy]

Well to keep it simple, 5.56 is the miltary designation and may be loaded to slightly higher pressures, .223 Rem. is the civilian SAMMI spec. Most guns shoot either just fine.

For twist rates 1:9 (one turn in 9") is about the current normal twist, suitable for bullets up to 70 grains or so. 1:8 is for using the very heavy bullets over 70 grains, normally used in long range match rifles and deer hunting rifles where you want to use the heavy bullets. Other twist rates, including 1:12 and 1:14, are used in rifles meant for shooting lightweight varmit bullets only, in the 40-45 grain range.

Bushmasters are fine, as is DPMS, Rock River Arms (RRA) and several others. If I was buying new today my choice would probably be RRA, I have a DPMS lower with my .50 Beowulf but the two RRA's I have shot were very fine examples.

AR's normally only become unreliable when you have unqualified people build them or work on them. You do have to keep them clean, the gas directly impinges in the action in order to move the bolt to the rear, this means carbon and other assorted crud can build up if you don't clean it out on occassion.

 

[c_yeager]

What's the difference between 5.56 & .223? I think I remember reading that 5.56 can take .223 but not the other way around, is that right?

In ar-15 parlance the difference typically indicates how the chamber is cut. A rifle chambered in .223 will be *slightly* smaller than on that is cut for 5.56. Conventional wisdom would have that the .223 chamber would have more potential for accuracy, while the 5.56 chamber would be less prone to failures to feed/extract. I think that in actual practice the difference is pretty negligable unless you measure your groups to the thousandth or your going into harm's way. I will say that if you plan on shooting a lot of dubious military surplus/milspec ammo that you will probably have better luck feeding it into a 5.56 chamber.

BG is correct about twist rates. This begs the question: "Why not just make everything a really fast rate so that this isnt an issue". I know there is an answere to that, but I dont know for sure what it is. I *think* that if a bullet is too light (short) that it wont have enough surface area to "grab" onto too drastic of a twist and will not stabilize properly.

 

[Alex45ACP]

Do you guys have ARs yourselves? What have been your experiences with reliability with yours if so? It's just that I've read so many horror stories about these rifles not working that it makes me hesitant to drop ~$800 on one...

But then I see pics like these:



and it makes me want to run out to the gun store and buy one today.

 

[lmccrock]

Read browningguy's response again. Bushmaster makes a good rifle; I have one that is perfectly reliable as long as I use USGI magazines, or the plastic ones from Thermold or Orlite.

Stick to a 1:9" twist unless you want to shoot matches (heavy bullets) or varmints (light bullets).

Rock River Arms (RRA) offers a "Wylde" chamber which is a compromise. I might go with thatfor my next upper; it is compromise between the 5.56 and .223 chambers. Also read http://www.ammo-oracle.com/body.htm for more details. The Ammo Oracle is long, but has the info you want.
Lee

 

[lmccrock]

Read browningguy's response again. Bushmaster makes a good rifle; I have one that is perfectly reliable as long as I use USGI magazines, or the plastic ones from Thermold or Orlite.

Stick to a 1:9" twist unless you want to shoot matches (heavy bullets) or varmints (light bullets). Some dedicated long-range rifles have a twist of 1:6.5" but that limits the bullet selection.

Rock River Arms (RRA) offers a "Wylde" chamber which is a compromise. I might go with that for my next upper; it is compromise between the 5.56 and .223 chambers. Also read http://www.ammo-oracle.com/body.htm for more details. The Ammo Oracle is long, but has the info you want.

Lee

 

[Dave Markowitz]

Do you guys have ARs yourselves? What have been your experiences with reliability with yours if so? It's just that I've read so many horror stories about these rifles not working that it makes me hesitant to drop ~$800 on one...

Don't believe all the AR-15 bashing you read on the Internet. A lot of it is repeating anecdotes dating from when the M-16 was introduced, when their were legitimate reliability complaints. If you get an AR-15 from one of the good manufacturers, maintain it properly, use good magazinzes, and use decent ammo, it will be reliable.

This is mine, a Colt AR-15A3 Tactical Carbine that I bought on 9/14/04:

 

[Gary G23]

The birdcage flash hider is the standard A2 flash hider. The Izzy is longer. The Izzy is mainly used on 14.5" barrels. When permanently attached it will bring the overall barrel length to a legal 16". If you look at the M4s on the Bushmaster website you will notice the Izzy version is shorter than the birdcage version. The M4 Bushy with a birdcage flash hider has a 16" barrel with a removable A2 FH. The advantage of the 14.5" barrel is that you can use a standard bayonet.

The internet myth that the AR is unreliable is way overblown. Both my M4s are 100% reliable. I'm sure there are unreliable ARs but these are mainly the ones that people try to build on the cheap and end up with what they paid for. IMO the keys to reliability are:
a good manufacturer
5.56 Nato chamber
chrome lined bore and chamber
USGI magazines
good ammo
Wolf extractor spring

I prefer Bushmaster, Stag Arms, and LMT.

 

[johnmcl]

Roger on Gary's Thoughts

Alex,

Gary tells you simply to find a good manufacturer with 5.56 Nato chamber, using a chrome lined bore and chamber, that handles USGI magazines and to shoot good ammo. Pay attention to him.

I've used the AR in war and a peace. It's a great weapon, despite what the internet bashers drool.

In addition to the manufacturers already listed, I would add Armalite. I'm very happy with the 20 in, A2 service rifle version that I have. I *love* that authoritative 'ka-bang!' when using the XM193 stuff.

Best of luck,

John

 

[Bartholomew Roberts]

I've never had any trouble with an unreliable AR except the ones I first built for myself - those were a little more problematic

The .223 and 5.56mm refers to the chamber of the barrel. .223 has a shorter throat than 5.56mm. Because 5.56mm is usually loaded hotter than .223, it will usually generate higher pressures with the shorter throat. Because most gas guns (and especially direct impingement) are pressure-sensitive, you can see reliability issues when shooting 5.56mm in a ,223 chamber (The gun is trying to extract while pressures are still too high in the chamber. This can lead to short stroking, fail to extract, extractor failure, ejector binding and a host of other problems). The length of the gas system also effects pressure issues and a carbine(M4) gas system will make any chamber issues even more noticeable.

I've been using the Wylde chamber in my newest barrel. It is a bit between the .223 and the 5.56mm and seems to work well; but I haven't had a chance to really shoot it yet.

As for manufacturer, almost every manufacturer occasionally puts out lemons and even the manufacturers I won't buy from largely produce good parts most of the time. I recommend you decide what options you want on the AR (since there are literally hundreds of configurations possible) and then purchase from the manufacturer who has those options. Often very few manufacturers will make a rifle with exactly the options you want.

I'd also highly recommend a flattop upper receiver. It is much more versatile than the older A1 or A2 style receivers. It offers you all kinds of optics mounting possibility and even if you only use iron sights, there are dozens of iron sights that mount on a 1913 rail, so you have more flexibility there as well.

I've had a few Bushmasters and they have always been reliable for me, though Bushy doesn't always do their QC as well as other manufacturers.