AR180 Bolt Carrier Group – Page 12

July 30, 2015

More AR-180 Upper News

Chuck at GunLab.net has been working on AR-180 uppers and has reverse engineered the trunion and has put up a very interesting article.

AR-180B Trunnion Design

I on the other hand, lacking any semblance of expertise in CAD took a differing approach when I reverse engineered my AR-180B upper.

Good friend of the site, Carl, sent me some square tubing that he has successfully used in his home builds. I decided to duplicate my upper using this material. It is much thicker wall than the original and I will have to shave this down at least on the bottom surface to get it to work with my lowers.

I did this for two main reasons. I wanted to refresh my skills on the mill as it has been many years since I last used one, and secondly, just to see if I could.

I made my first trunion out of 6061 aluminum just to test my measurements out and I have found that a few needed to be adjusted.

I learned a lot from this project and I find things like this much more rewarding than the usual beginners projects.

I will continue to tweak this until I am happy with it then I will start a new one using the first as a template. I think I will make the trunion out of 4140 unless y’all have any advice.

Some pictures that show what I have been up to for the last two days.

Some things to note if you attempt one of these yourself. The interior of the tubing is not perfectly square so some hand fitting will be necessary. The tubing spreads open once the bottom is cut. Some method of squeezing it back before welding would have to be considered. Lastly, all of this will be rendered moot once Chuck makes new uppers and flats available. Until then I will use this as a way to improve my machine skills and better learn my tools.

July 20, 2015

New AR-180 Uppers?

It looks like Chuck over at the GunLab has got his paws on an “In-The-White” AR-180 upper and if you know him like I do, that means we might be seeing some new uppers available soon.

I called him and we chatted for quite a while. He is hoping to make a run of these and offer them complete with trunion welded in but nothing on top. No dovetail, no rear sight. Perfect for those who want to build your own AR-180C flat top clone. He also is planning to make a run of flats.

I look forward to the day when the hobbyist like me, and many of you, can build our own AR-180 from scratch. That day may be closer than you think.

180B Upper

July 8, 2015

Full Auto AR-180 Conversion on Gunbroker

I was alerted to this interesting full auto AR-180 conversion by a reader and I contacted the seller to get more information. I had assumed that all conversions used the same system as the AR-18 but my research shows that there are many different ways to get the job done.

Gunbroker

This particular gun also brings to light the crazy gun laws that we have to deal with and in particular those surrounding full auto guns in Connecticut.

First lets see how an AR-18 worked.

You can see in this picture that the upper receiver has two tabs that retain the auto sear. A link is attached to the sear that rides along the bottom of the upper and is tripped by the bolt carrier. The sear acts upon the rear of the hammer. The hammer is different than the one used on an AR-180 as is the disconnector, bolt carrier, and firing pin.

This conversion goes about it in a completely different way.

This conversion is on a Howa AR-180 and it has a sear that acts on the front of the hammer. It appears to have a pivot added to the front of the fire control box and you can just make out the pin location in the picture above. The sear has a tail that is tripped by a piece that was welded on to the bolt carrier. It uses all the original 180 fire control parts with the exception of the disconnector and the safety. The 180 firing pin is also retained.

I wonder if this is how the Widowmaker conversions were done?

Now for the Connecticut twist on this story. It appears that those who drafted their assault weapons ban tried to get machine guns classified as assault weapons and in doing so, left the door open for guns that are full auto only. You can’t own a registered select fire weapon (one that fires Safe/Semi/Full) but you can have a papaered Full auto machine gun (Safe/Full). This gun is one such animal. For those that live in other states, it can be converted back to a select fire configuration.

Please feel free to comment about any conversions you have come across. I think this is a very cool part of the history of the AR-180.

June 15, 2015

Latest Happenings at AR180S.com

I just wanted to touch base with y’all to let you know what has been happening. My new job has kicked into high gear and it has me out of town most weeks and that has the unfortunate side effect of keeping me away from the blog. I am home this week and hope to have an article of substance before I head back out on the road.

A couple weekends ago I found a reasonably priced Mill/Drill on craigslist. Unfortunately it was a 4 hour drive away. I rented a trailer and my wife and I went on an adventure to go pick it up. It had lead a relatively hard life as a drill for an off-road fabrication company and would need a little TLC. What can I say, I am a sucker for a project.

It is a Jet JMD-18 and it is the perfect size for my home shop. Being a round column it will require special consideration to order of operations to reduce the need for raising the head.

Got it home and it took some doing to get it off the trailer without a cherry picker but we got ‘er done.

I had originally intended to modify my drill press and use it for small milling jobs so I had purchased a cross slide vise from Harbor Freight but it just didn’t work out. I returned it and picked up a chain fall that allowed me to put this mill on the table.

I pulled the spindle apart to get the number off the bearings and put in an order with McMaster Carr. That finished off my weekend as I had to pack and leave town the next morning.

Last weekend the bearings were installed and a run in procedure was initiated.

The head is back together and it runs much quieter.

Cleaning now starts on the table. It stayed locked in one place for years it would seem, so the ways are a little cruddy. A little bit of rust needs to be cleaned off the surface.

Chuck over at the GunLab keeps cranking out the AR-180B parts and I am hopeful that I will have some kits in my hands soon. Several have emailed me stating their interest and I will be starting up a waiting list. Email me through the contact form and I will put your name on it.

I am also juggling several gun projects myself. I am now on the fence about the 458 SOCOM AR-180B, it may turn into a mid length gas carbine in 5.56. I already have the barrel so it will be cheap but not nearly as cool. I have a Sten MkIII kit that I want to work on after I get the mill up and running. I also want to try my hand an an 80% lower. Not sure which way to go with a buttstock for the AAA SAP. Folder, original, or mill one out of Delrin?

On top of that I have to prepare for a new Advanced Electrical class I am teaching next week and attend a teaching workshop this week.

Brain Overload.

May 29, 2015

New AR-180B Parts are Coming

Big shout out to Chuck over at GunLab.net who has started work on AR-180B parts. First up is the safety and he has worked out an awesome two piece design.

First some pics from Solidworks.

Here is a video of the safety lever being made.

And a couple pics of the actual part.

Yep, there will be a few available.

The plan is to offer a set of parts that will supplement your AR-15 lower parts kit and allow you to fully populate a Nodak NDS-18S. Previously the only way to do that was to buy a complete AR-180B Rifle and strip out the lower parts. This will allow you to buy a lower, AR-15 lower parts kit, and this lower kit and get a working lower for your AR-180B, AR-180, or Vulcan V18 upper.