So why the AR180?

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isaidme

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Other then looks what makes the AR180 different the an AR15?I know the lower is polymer but what else?Any oppions on these?
 
Two major differences in the operating system, both of which make the AR-180 more functionaly reliable than the AR-15.

- The action is cycled by a gas piston attached to the bolt carrier, which prevents gas and debris from being cycled through the bolt.

- The bolt carrier rides on a pair of steel guide rods instead of on the reciever. Less friction and zero reciever wear.

One more difference, the AR-180 has a fixed reciprocating bolt handle, which can be used as a forward bolt assist. The AR has a seperate forward assist.

A few other minor ergonomic differences.

- Chris
 
isaidme,

The polymer lower AR-180b is just a new clone. The original was all stamped steel with plastic furniture. It bears a close lineage to the FN FNC and the SA-80. The new HK G36 is also internally similar, but is all plastic, rather than all stampings.
 
One more difference, the AR-180 has a fixed reciprocating bolt handle, which can be used as a forward bolt assist.

...and also an effective tool for fracturing unwary digits! :D (It also makes an impressive cloud of wood shavings when inadvertently fired from close left-hand barricade scenarios... :eek: )

(Of course, this is true of most any rifle that has high-velocity reciprocating doodads flying about the external parts of the gun. It's easily remedied via training and just not putting your hands in dumb places, but can scare the pants off those unfamiliar with it...)

(PPS: One thing I dearly love about the charging handle arrangement of nearly every military rifle other than the AR/M16 is that you can kick the bolt-handle to the rear. I've never had to use "forward assist", but I've more than once had to extract stuck or torn cases; it's nice to not need to tear the rifle down to do that...)
 
- The action is cycled by a gas piston attached to the bolt carrier, which prevents gas and debris from being cycled through the bolt.
The Piston is separate from the link which is separate from the operating rod which is separate from the bolt carrier. The link rides a ball-joint surface so that the operating rod can be free to flex. It's a very lightweight part and would otherwise need to be as heavy as an FAL rod to work properly. The reason for having three pieces is to make the whole assembly lightweight and reliable.
One more difference, the AR-180 has a fixed reciprocating bolt handle...
Well, it's not really fixed. It rotates around in the bolt carrier. Regardless, what you said about the forward assist is true.

The differences are more major than that though. In operation, changing magazines is much more difficult. You have to remove the right hand and the left hand from the pistol grip unless you turn the gun sideways or cross your left hand over to operate the bolt handle. Armalite copied the AR-180's lack of an external bolt-stop latch. Charging the rifle requires you to reach up with your right hand or over with the left to pull the bolt sligthly back and then release.

Other differences? No gigantic buffer in the buttstock and it doesn't need a two pound spring to operate. The sights are much more basic. Scope mounting is more difficult. There are no heat-shields in the handguard which allows it to get hotter MUCH quicker. The front pivot pin loosens up quickly and makes the gun feel wobbly. Not saying I don't like the gun, but it's not a similar gun other than caliber, magazine, and trigger group.

It bears a close lineage to the FN FNC and the SA-80. The new HK G36 is also internally similar, but is all plastic, rather than all stampings.
It bears DIRECT lineage to the SA-80 to the point that the British at one time owned? (not sure) the rights to production of the AR-180 and simply copied much of its design. In the process, they made it LESS reliable. Leave it to the Brits. The FN FNC owes none of its lineage to the AR-180. It's more directly related to the AK although you might see some external similarities. You're right about the HK G36. It rides on one rod instead of two. Strangely, this was a discarded Armalite patent. They chose two rods because they didn't want other doohickeys to stabilize the bolt inside the receiver. Sheet-metal receivers can dent and they didn't want a dent jamming the rifle. Plastic doesn't dent.

The G-36 is much more than an AR-180 gas system though. It moves the relief system to the front of the gas piston. A nipple protrudes through the front of the gas block. When sufficient gas has escaped to work the action, excess is vented through the front of the block. The piston also utilizes AR-15 type gas rings to seal much better and allow simple replacement of the rings instead of rebuilding worn gas systems.
SL8gas.jpg
 
Charging the rifle requires you to reach up with your right hand or over with the left to pull the bolt sligthly back and then release.

Only for you righties. I happen to like the AR-180s system of operations.

As for other things...handguards, scope mounts...give it time. If the weapon becomes popular (at least as popular as the Mini-14) the all sorts of aftermarket accessories will be made for it.

One neat thing about it is that it has seperate upper and lower receivers, like the AR-15. If anyone makes a different upper, it'd be no problem to swap them.
 
...and also an effective tool for fracturing unwary digits! (It also makes an impressive cloud of wood shavings when inadvertently fired from close left-hand barricade scenarios... )
True, true, true, and one of the reasons that I no longer have my FAL. I had gotten used to wraping my thumb around the bolt handle, which is fine for a fixed charging handle. For a reciprocating one...ouch.

A combat rifle really needs to have either a very positive forward assist or a fixed bolt handle. It's next to impossible to clear a misfeed otherwise.

Badger - Interesting pic of the G36 gas system. Does it self-regulate like the M14, by any chance?

- Chris
 
I liked the AR180 I purchased until it decided on round100 or so to break in half at the upper/lower reciever pivot point. Armalite fixed it but the gun does not leave me with a warm fuzzy fealing anymore.
Pat
 
One thing I dearly love about the charging handle arrangement of nearly every military rifle other than the AR/M16 is that you can kick the bolt-handle to the rear. I've never had to use "forward assist", but I've more than once had to extract stuck or torn cases; it's nice to not need to tear the rifle down to do that.
Been there, done that. Usually with a few choice words spoken towards that particular FAL that I'm not allowed to repeat amongst this company...
 
Badger,

You're right about the FNC, I was just trying to relate the AR-18 to other gas piston sheet steel guns, rather than milled designs (FAL, AK) or alloy (AR15, K2). The AR-18 was one of the first decent gas guns made from stampings, and it's basic form has foretold (if not inspired) other designs besides the SA-80, Type 89 and G36.
 
Badger - Interesting pic of the G36 gas system. Does it self-regulate like the M14, by any chance?

I'll have to read the patent again. IIRC, it is not intended to self-regulate. By that, I assume you mean that in adverse conditions more energy will be applied to the bolt carrier. I do believe this is true of the design inherintly although I was under the impression that this was more of a problem in belt-fed guns.
 
Is everyone talking about the same rifle? It doesn't seem like it.

Some comments. The gas piston system of the AR-18/180 is a direct copy of that used in the SVT40 and G.43. It is not the same as the Saive system although the medium stroke piston is the same general idea.

I don't know about the AR-180B (I have been trying to buy one, without success), but the bolt handle of the AR-18/180 does not rotate in the carrier. It stays fixed.

As to the bolt handle hitting things, the same is true of rifles like the M1, M14, AK-47, and dozens of other self loading and selective fire rifles. I prefer a bolt handle I can use to close the bolt, or stomp on to open it, to the enclosed and fragile AR-15 system.

The system is not like the FAL. The FAL uses a rear locked, dropping bolt, where the AR-18/180 uses a rotating bolt like the AR-15/M16, but without the dirt created in the AR-15/M16 by channeling spent gas through the bolt carrier.

I have long felt that the AR-18/180 is what the AR-15 should have been. Cheaper, easier to make, easier to use, easier to maintain. The stamped components of the original rifle would have allowed mass production at a third the cost of the AR-15/M16.

And yes, there is a built in scope mount, and a good one, perfectly adequate for a service sniper rifle.

Jim
 
The gas piston system of the AR-18/180 is a direct copy of that used in the SVT40 and G.43. It is not the same as the Saive system although the medium stroke piston is the same general idea.
The gas system of the AR-18 is NOT a direct copy of the SVT40 and G.43. In fact, it is a different design. Yes, they all have connecting rods however the AR-18 is different in the way and purpose for the part. The AR-18 was designed so that the connecting surface between the link and moveable piston was a 'ball-joint' surface. The patent states:

It is the object of this inventioin to provide a lightweight push rod for a gas-actuated push rod system through the reduction of the diameter of the push rod which can bend freely in operation without impairing the operation of the system or causing malfunction of the system.

If rapid fire causes push rod (4) to bend or whip, the forward end will merely move with respect to the cylinder (11) on spherical surface (12), and no bending or stress will occur between cylinder (11) and piston (7) that will tend to gall and produce malfunction

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AR180OperatingGroup.jpg
AR180OperatingGroupAssembled.jpg

This is a significant change. Previous systems such as the German and Russian Systems relied on play and looser tolerances to accomplish the same thing. These were genearlly looser guns and suffered accordingly. While similar, the difference is significant in its conception.

Yeah, blah, blah, blah. What it means is that the AR-18 gas system takes up less room and is SIGNIFICANTLY lighter than that of the FAL or Kalashnikov types.
 

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The patented "ball joint" feature may allow use of a lighter and more flexible op rod, but that doesn't make it an entirely different system from the G.43, nor does it make it like the FAL system or the Kalashnikov system, which are not only not at all like the AR-18 system but are very different from each other.

I wonder if the "ball joint" is really needed, or if the op rod can be lighter simply because the cartridge is less powerful than the 7.9 or the 7.62x54R and the operating parts lighter. Might be interesting to make a non-ball joint set up and see what happens.

Jim
 
Jim

Agreed, it might all by hype. But then again, if it is hype H&K bought into it as this feature is built into the G36 in addition to their other features.

You're right, not entirely different from the other two guns. There is very little new under the sun. Armalite might have had a different motive for doing this though. I don't know if there is any primary research that would suggest the Germans and Russians were intending to lower the weight of the gun without sacraficing the durability of the operating rod. Seems like they all could have come to the same conclusion separately.
 
Pay under $600 and, yes, from what I've seen they are good guns worth the money. You can expect more in terms of accuracy and satisfaction than from the Mini-14... that's my opinion and I own two Mini's.
I wonder how many times it can bend before it fails?
Before what fails? What's bending? Did I miss something? If you mean how many times the operating rod can bend before it fails... It's not bending in the sense you mean, it's bending as a tuning fork bends. When was the last time you saw a tuning fork break? Most other parts of the gun will fail before the operating rod does.
 
Keep in mind that when Armalite came up with the op-rod design they were working on the AR-16 which was a 7.62X51 weapon. The little gun came later so it is not just that the caliber is smaller.
 
I'll quote the only test I know of which compared two weapons of a similar manufacturing background... that is they were both made about the same time with the same techniques and materials. The 1965 Gun Digest has an article comparing the AR-10, AR-15, AR-16, AR-18, and FN-FAL. The accuracy potential was measured by average 10 shot groups. This is a more realistic measure of accuracy in my opinion than somebody's best 3 shot group from 10 groups. Anyhow the numbers were:

AR-10: 3 7/16"
FAL: 3 1/4"
AR-15: 3 5/8"
AR-16: 4 1/4"
AR-18: 3 3/4"

In all fairness to the AR-16, this was a prototype weapon and one of few made. It was the least developed of the arms tested. Certainly the AR-15 can get better with 40 years of development whereas the AR-180 (semi-auto version of the AR-18) has been largely overshadowed by its older brother.

As a side-note, the British are quick to brag about the one feature their version of the AR-18 does have. The SA-80 / L85 rifle is a very accurate rifle when it works. The British use the AR-18 gas system in that gun.
 
I imagine the 1965 tests involved barrels with slow twists and lighter profiles.

As there are numerous versions of the AR15, and only a few versions of the AR180, there is likely more than a few AR15s that are going to be much more accurate than the 180.

But, like BA points out, the SA80 is about the most accurate NATO rifle right now. The G36 is also supposed to be great.

I would conclude from that that the AR180 COULD be quite accurate, but that doesn't mean any example you happen to run into will be. The FAL design isn't considered the Gold standard of accuracy, but DSA FALs are really accurate. So execution has a lot to do with it.

In fairness to the AR15, it does have the most "free floating" gas system possible, which always helps.
 
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