I’ve often thought about a drop-in trigger for my AR180B Shorty Project, The AR180S.
Reader Matthew asked about one for his Nodak lower and I had to tell him to proceed with caution because I was not sure if they would work.
I was concerned about interference with the bolt hold open assembly.
As luck would have it I was picking up an AR180B at my local FFL and knew he had used drop in triggers in some of his guns. He let me borrow one to try in my gun and I am glad to report that it fits!
What he let me use and at this time the only one I can recommend is the Patriot Ordinance Factory 4.5 pound single stage with standard trigger shape. Click here to read more about it.
I will report back after I shoot it but dry fire and function check work flawlessly so far.
The best part is, it includes KNS anti rotation pins so that will save you a few bucks. You can used the included side plates and just order the longer pins. Read more about the pins here.
Surfing around and I found that Joe Bob Outfitters has these POF-USA Drop In Triggers for $149.95 shipped and it includes an AR15 lower parts kit. That looks like a smoking deal, click here.
Please reply if you have successfully used any drop in triggers in your 180B or Nodak lower. I would like to let readers know about all the alternatives out there.
Josh at Stormwerkz.com just posted on Instagram that his Type 2 AR180B stock adapters are back in stock.
He has also improved them with the addition of a set screw to locate the receiver extension. That will be very helpful as getting the butt stock lined up when tightening the castle nut was a pain.
Check out these adapters as well as lots of other cool stuff on his website. Click here.
These are a perfect addition to the Nodak NDS-18S lower and if you install a pistol tube first, you can always build your gun as a pistol at a future date. Even if you build it as a rifle now. I don’t make the rules, I just follow them.
I have a few Lower Parts Kits left in stock with no plans to do a second batch in the near future. Now might be your last opportunity for quite some time. Shoot me an email at Rick@AR180S.com to order. $125 shipped, PayPal slightly higher.
The goal for this pistol build is to make an AR180B upper that will work with an original lower as well as the NDS-18S.
I have had several readers ask if such a thing is possible and I know that it is, but until now I didn’t know exactly what mods need to be made. This upper will be my Guinea Pig.
I also have to avoid any problems with building an illegal SBR till I get a stamp for my Costa Mesa lower.
Here is my process as I see it. The 180B upper will not physically fit on an original lower do to clearance issues around the front pivot pin. I also feel that I can fit the stripped upper to my lower if it does not have a barrel installed. I will test fire the original lower with one of my original uppers and test fire my pistol upper with my new pistol NDS-18S lower. Never will the two fully meet till after the stamp comes back.
I am starting with the stripped lower that I got at the last SAR West show. I finally found most of the fire control parts and it should be ready for testing soon.
Just a quick mock up to show you what I hope it will look like down the road.
Compared to the original AR-18S
This will also apply to those looking to put a 180B rifle upper on their original lower.
First issue is the clearance issue around the front pivot pin. The sides need to be milled down some to clear the ears on the lower. The second issue becomes apparent as soon as you attempt to mate the two. The guide rod assemblies are not the same between the 180 and the 180B.
The NDS-18S gets around this by having holes to accommodate either assembly.
The original lower only has provisions for the upper holes. I considered drilling a new hole but decided against it.
You might think to yourself, why not use an original guide rod assembly in the B upper.
The rear sight is narrower on the B upper and that won’t work either. I am hoping I can come across a messed up original that I can make work or I may be forced to modify a B guide rod. I’m not opposed to modifying them but it looks like a royal pain to do.
Just finished installing one of Josh’s charging handles on my AR-180S Shorty and I’m really loving it.
A quick couple passes with an 1/8″ endmill to open up a slot and she fits like a glove.
This unit is very well built and reminds me a lot of the early Howa charging handle.
Check out the charging handles here as well as many other cool AR-180 and AR-180B parts and accessories.
Reader Michael sent me an email telling me about KNS Precision’s extended length fire control pins. They are designed to work with the Kaiser US Polymer Lower which has the same dimensions as the AR180B. These could also be used in your original AR180B lower.
I ordered myself a set along with some sideplates and they look like the cat’s meow. I could not be happier with the fit and finish. They are the perfect length. Range report to follow. FYI this gun ran flawlessly with the Colt 901 pins during my last range trip.
It has a new nickname, Thumper. Anyone who has shot a 5.56 SBR under cover at the range can probably relate.
KNS sent my order out very quickly. I ordered it on 3-16 while out of town and when I got home this morning it was already waiting for me. Top notch service.
If you are on the fence about building a Nodak NDS-18S, I think this is the last piece of the puzzle.
Lower Parts Kits are still available for $125 shipped (PayPal slightly higher). Just send me an email. Rick@ar180s.com