Heads Up: Interesting Costa Mesa AR-180

While making my daily scan of Gunbroker.com I can across this interesting Costa Mesa AR-180.

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I had seen it before and dismissed it as a mixmaster gun with a Howa lower or it was using a former AR-18 lower.

You will notice the markings around the safety selector and the fact that the safety stops would allow for 180 degrees of movement.

I was able to figure out the serial from this picture as S3803.

AR180 Serial

I had to blow it up but I believe it is legit.

I surmise that the Costa Mesa plant was using up all the parts on hand and they used a lower that was originally intended for an AR-18 on this gun. This makes sense when you consider that the last Cost Mesa AR-180 serial was S4067 so this was probably built in the last month of production.



First Generation AR-180 Scopes

The first generation AR-180 scopes are easy to identify if you know how.

They are marked in meters.

AR-180 Scope Meters


The reticle is of the inverted post style.

AR-180 Scope Inverted Post

The practical uses of this style reticle is mentioned in the manual.

AR-180 Scope Manual

To quote from the manual. “The sight incorporates an inverted post as well as fine cross-hairs. When “holding over” at extreme ranges, this precludes the post from blotting out the target.”

The final distinguishing mark that this scope features is a serial number on the bottom of the base. These will all start with 67 followed by four digits.

AR-180 Scope Serial 670037

My good friend and AR-180 mentor, Rich, has collected all the scope serial numbers he has come across over the years and has found none that are higher than 671000. He has further deduced that these were originally produced for the first 1000 Howa rifles.

Armalite never wanted to go into production and make guns as much as they wanted to design them and then license the rights to others to actually produce.

The fact that they had Howa Machinery produce the rifle is documented in the January 31, 1966 issue of U.S. News and World Report. One small paragraph under the heading “Rifles for Asia” reads.

“Armalite, Inc. the Costa Mesa, Calif., firm that took over the former Fairchild gun division, has developed a new combat rifle, the AR18. This model is to be produced by Japan’s Howa Machinery, Ltd., under a provisional agreement. It would be the first mass production of this rifle, with the Japanese expecting to export some units to such Southeast Asia customers as Thailand and the Philippines.”

Original article found hereĀ 

After Howa produced the first 1000 rifles but before they could ship, Japan became neutral and would not ship any guns to nations that were in active conflicts.

“Adopted in 1967, the three principles originally prohibited arms sales to Communist nations, countries under United Nations sanctions and countries in armed conflict, but it eventually grew into a blanket ban on all weapons exports.”

From NY Times article.

Early Howa AR-180’s are known to have been converted from AR-18’s so this is the series of events as I have come to understand them.

Howa produced 1000 AR-18 rifles in 1967. They were complete with serial numbered scopes and flash hiders. The Japanese government changed policy and they were not allowed to export them. The Costa Mesa plant was forced to ramp up production and in order to offer scopes as add on accessories, they imported the scopes from Howa as these were not under any sanctions. These scopes were offered up, in plain cardboard boxes, to any who ordered them with no thought given to matching the serial numbers.

AR-180 Scope Box

Picture found via Google Image Search

In conclusion, this makes for a pretty firm number of these early scopes not counting losses over the years. Less than 1000. Identifying and distinguishing them from the later scopes is pretty straight forward, marked in meters, inverted post reticle, and a serial number starting in 67.

Good hunting and please let me know if you have any pictures of original scope boxes you would like to share.

Please note I have manually added a few email addresses to my subscriber list, let me know if this is a problem and I will gladly remove them.


Armalite AR-180 Owners Manual Variations

After chatting with my friend Rich today, he mentioned that the Armalite AR-180 Owners manual he is selling is from the Sterling era and the early manuals are different.

I dug my original manual that came with my Costa Mesa gun to see for myself. There are definitely variations in these manuals that we can use to see what guns they would have came with originally.

First, the covers. The only thing notable on the front is the outline runs off the bottom of the page on the early manual and creates a box on the late manual.

AR-180 Front Cover

The rear covers are much different and should be a perfect indicator for those who are looking to get the correct manual for your gun. The early manual does not feature a picture of the rifle as the later manual does.

In the first two pictures the late manual is on the left, in the remaining pictures it is on the top.

AR-180 Back Cover


The inside front cover is different as well. You will notice the outline forming a box just like on the cover. This is consistent throughout the manual. There are also several things added to the late manual. A warning about the use of reloaded ammunition on the inside cover. A congratulations paragraph at the top of the first page. Finally the logo and address added to the bottom of the page.

AR-180 Inside Front Cover


On page one the logo is added and the lower left picture appears to be inverted on the late manual.

AR-180 Page 1


On page five the picture in the lower left is a slightly different version noted by the thumb position on the magazine release.

AR-180 Page 5


On page 7 all the pictures except the lower right are slightly different.

AR-180 Page 7


On page nine the picture in the lower left corner is completely different.

AR-180 Page 9


On page 11 all the pictures show some differences.

AR-180 Page 11


Page 13 has different pictures and section 5-2A is added dealing with steel magazines. Page 14 has different pictures and the wording in section 5-4 is changed to reflect the different reticles in the late scopes. Crosshair vs. inverted post.

AR-180 Page 13


The rest of the pages remain unchanged until page 22, it has three extra items listed, 20,30,40 round mags, as well as a picture.

AR-180 Page 21


The inside back cover is blank on the early manual and features added safety precautions and address on the late manual.

AR-180 Inside Back Cover


I believe there are some transitional manuals as well where some of the info was added in the form of inserts or glued onto the pages as well.

If anyone has any other versions please let me know via the contact page or comment below this post.

Thanks again and sorry for the lack of updates lately but I caught a cold from hell flying back from Orlando after Thanksgiving and I couldn’t collect my thoughts enough and put together a coherent post.


Heads Up: NOS AR-180 Manual Package

My friend Rich is selling some NOS AR-180 Manuals with bonus copies of some other manuals and inserts over on gunbroker.

I received a couple of these packages in a trade with him and I can tell you they are top notch.

His asking price is less than I feel the NOS manuals should go for so act fast before they are all gone.

AR-180 Manual Package

He is a great guy to deal with and a longtime AR-180 collector who gives his knowledge freely and without hesitation.

Tell him BigRix sent you.

AR-180 Manual PackageĀ 

AR-180B Shorty Project Pt. III

The next part that had to made were the hand guards. I first mocked them up to find the approximate length then cut them off with my bandsaw. I left them a little long and figured I could trim them if I had to.

I then trimmed a small piece of the front end of the cut off part and fitted them into the hand guard. This will allow me to use the existing end cap.

AR-180S Inside Bottom Handguard AR-180S Inside Top Handguard

Here you can see that I didn’t get things exactly right as there is a small gap at the front of the hand guards. They will work for function testing but I intend to build a set of new end caps that encapsulate the entire hand guard.

AR-180S Left

Here she is ready to head to the range and dial in the gas port size.

Featuring a Stormwerkz mount and Primary Arms Micro Red Dot.


Primary Arms Micro

I would also like to ask if everyone could help me test out the site by leaving comments so I can see if it is working.