A local gunshop has a Armalite AR-180 for sale for $800.  I don't know much about these rifles but it looks pretty cool.  

Who can tell me about the history of these?  What countries used these as military weapons, if any?

It says Sterling, Great Britain and Armalite on it.  It has a hinged folding stock, bayo lug & open-end flash suppressor.  It doesn't look like a kit gun.  It has a 20 rd mag that looks almost exactly like a M16 mag but locks into the receiver on the opposite side so is not interchangeable.

Condition is about "very good" condition, it shows a fair amount of use but not abuse.

No country officially adopted them as a battle rifle. Though they did earn the dubious nickname "widowmaker" in Northern Ireland.

The mags can be made from AR-15 mags so that is not an issue. Armalite is currently marketing the ar180B as the new style. It has a polymer lower receiver.

That said I have never owned one of the original 180s. But I love my 180b. It is accurate and gas piston operated.

Quoted: A local gunshop has a Armalite AR-180 for sale for $800.  I don't know much about these rifles but it looks pretty cool.   Who can tell me about the history of these?  What countries used these as military weapons, if any? It says Sterling, Great Britain and Armalite on it.  It has a hinged folding stock, bayo lug & open-end flash suppressor.  It doesn't look like a kit gun.  It has a 20 rd mag that looks almost exactly like a M16 mag but locks into the receiver on the opposite side so is not interchangeable. Condition is about "very good" condition, it shows a fair amount of use but not abuse.

800 is a fair price, if you go by listings on gunbroker etc,

can't remember the #'s offhand, but i think sterling made the most, the other manufacturers were costa mesa, and howa

they were developed as a m16 style weapon for countries that did not have the capability to cast or forge aluminum receivers,

the mags are almost the same as you noted, you can convert M16 mags very easily

ask your question over on the ar10/ar180 forum in the ar15 section, you may get more replies

FWIW i have an ar-18 (NFA version of the 180) great shooting guns,

Quoted: Who can tell me about the history of these?  What countries used these as military weapons, if any?

Parts of Ireland did.

Thanks, everybody!  Interesting weapon!

My friend had one of the new ones and let me put a few 100 down range with it.

It was very, very light.

Handled well and was comfortable.

Bolt carrier rides on two rods, each with a recoil spring around them. The bolt is M-16/AR-15 style multi-lug. FAL type gas piston.

Recoil like a 20" AR.

Very accurate and easy/fun to shoot.

Easy to feild strip and maintain.

Handgaurds felt cheap and thin.

Didn't care for the polymer lower either, but it did work.

I've got an original Costa Mesa AR-180, and it shoots great. Very nice. The Costa Mesa, CA ones were the first made, if I remember correctly, and they later made under license by Sterling in England (who promptly appear to have stolen the bolt/carrier design for use in the SA-80/L85), and by Howa in Japan. Interestingly, the action of the HK G-36 appears to be the same, or very, very similar. So, while the AR-18/180 wasn't adopted by any country, it influenced designs that were.

Get the original 180. It's all metal and built for rugged military type use. The lower of the new 180b is plastic and I promise it's not designed to go through military trials the way the original one was.

$800 isn't a bad price. For a while Numrich was selling original 20rd mags for a very reasonable price. You might want to see if they still have any. Numrich  -  There were some nice original 30 and even 40 round mags for them too, but they are hard to find now and quite expensive when you can find them. I have one of the original 40's and it functions flawlessly. Another thing you might want to look for is some of the older (waaay pre-ban) aftermarket AR15 mags that also had the right side slot for the 180 mag release. I have several that (I think) were made by precision (pmi) and they work great. Also, as mentioned above, you can very easily modify usgi AR mags to work. If you have access to a milling machine, that would be great, but if not, just take an original 180 mag and stick a piece of masking tape on the side of it running from the top of the right hand feed lip down to below the mag catch slot. Now mark the position of the top edge of the feed lip and the position of the mag catch slot with a pen. - Take the tape off of the original mag and put it on a standard AR15 mag, making sure to carefully align the top pen mark with the top of the right side feed lip. All you have to do now is use a dremel tool to buzz out the 180 slot where the other pen mark is. Simple, quick and easy. I should re-state though, that you need to make sure to get the alignment right, or you'll end up with a slot that's at the wrong height. Take your time and it'll work perfectly.

Did I say I love my 180?

I love the tape suggestion for making ar mags work!  It would be hard to go wrong that way...thanks!

You're welcome. I found that idea on an old ar180 website (at sterling webpages) that appears to no longer exist. It was really the best 180 site on the net, and was dedicated to the original rifles. I guess it just faded away after the 180b came along. I don't know for sure. Anyhow, I've done quite a few ar mags that way and only messed one up... when I got in a hurry and didn't pay close enough attention to lining up the upper line with the mag lip. [edited to add that if you're going to make an error on the mag slot height, try to err on the side of placing it a little too low... that way you can always slowly take more material off the top side of the slot until you get proper fit. If you place the slot a little too high to begin with, there's no way to save it short of welding the aluminum back up, which would not be easy to say the least]

You'll really enjoy the 180. Very fun to shoot and well balanced as well.

The British Army did not adopt it as a main shoulder arm, but they did use some and issue them to the SAS and other units.  I had heard that the Howa (Japanese made) were the best.

Hmmm, I thought I read that the Costa Mesa (US made) ones were the best. Or at least worth the most. Maybe that's because there were fewer of those though. To be honest, I can't remember that well, 'cause I read all that stuff a long time ago. I sure wish that old ar180 site was still up, 'cause it had a really good history section where all of that was covered. The only thing I definitely remember about the howa ones was that there was some sort of big fuss over the export of them from japan and they were forced to stop.

Maybe the guy who used to run that other (sterling) site will see this and post something. I'm pretty sure he used to talk about things he saw here, so maybe he'll see this?