Retro & Master thread:  https://www.ar15.com/forums/AR-15/Collecting-the-AR-a-30-minute-presentation/123-730817/
M-16 thread:  https://www.ar15.com/forums/armory/Collecting-cloning-building-using-hunting-with-the-AR-15-a-presentation-Input-requested-/23-495279/
A2 thread:  https://www.ar15.com/forums/ar-15/Collecting-cloning-building-using-hunting-with-the-AR-15-a-presentation-Input-requested-/127-734514/
BIY thread:  https://www.ar15.com/forums/ar-15/Collecting-cloning-building-using-hunting-with-the-AR-15-a-presentation-Input-requested-/4-734515/
Original thread (archived):  https://www.ar15.com/forums/AR-15/Collecting-the-AR-a-30-minute-presentation/123-730817/

So, I know a RDIAS is a Registered Drop In Auto Sear, and a RLL is a Registered Lightning Link.  But how do those differ from each other?

So, on 3 January, I am making a presentation to my local arms collecting society about collecting, and other uses of the AR-15, and why it's so popular.

I'm starting a thread here, and will also post in a couple of other sections in the AR-15 forum, soliciting input.  The master thread is in Retro, linked above.  I'm aiming for 30-40 minutes, in Powerpoint format, and will post the final product at the Feinstein Project.  I'm posting here b/c the M-16, whether in RR, RLL, or RDIAS form is an important and expensive part of AR-15 collecting, and I want at least a slide or two mentioning the various types and their differences.

I'll get some bullet points up over the next few days, in between painting my step-daughter's 27" pencil bbl AR and gluing & oiling my Da's IBM wood for Christmas.

I'm sure y'all have FAR more information than I can fit in a 2 hour presentation, let alone a 40 minute one, but post whatever you think might be useful, and I will skim 8.7% of the information you present off the top.

If anyone in the north Texas area would like to bring any part of their collection out, post up and I'll IM you w/ the exact location & date.  I'll need your actual name, so I can introduce you as a visitor.  I expect the gun will need to be tied according to club rules as well, so someone else will have to get their grubby hands on it.

ETA:  Working copy of PowerPoint presentation (.ppt) downloadable @:

http://www.FeinsteinProject.org/misc/AR15Jan2019.ppt

What is the difference btwn a RDIAS and a RLL?  Any practical difference, or just slightly different mechanisms?

In a hurry, but the LL will work in any low shelf AR using a SP-1 bolt.
The RDIAS  requires an M-16 fire control group and M-16 bolt.
The LL does not permit select fire but can be modified to semi and auto fire.
Lastly, the LL is around 15 K, the RDIAS around 35K.
Will check back.

Very helpful, thanks.

Sent a pm, but here has a lot of info. I have an RLL. Main is Dias uses factory m16 parts and basically holds an auto sear in the same place as the third pin hole in a registered reciever, making it behave exactly like an m16.

Rll is a trick, it uses the back of the upper reciever as a pivot to pull the disconnector off the hammer when the trigger is back, using a SP1 profile bolt carrier and a little paddle that sticks up as a lever. In a semi trigger group, you drop it in and instant full auto only, if you want safe/semi/auto you can modify a three round burst FCG that has two disconnectors, in semi you have one unmodified disconnector still holding the hammer back, in auto the selector disconnects that one and so you get full auto

https://www.ar15.com/forums/Armory/RDIAS-vs-RLL-vs-RR-pros-and-cons/23-199903/

http://www.quarterbore.com/ar15m16/index.html

Thanks fellas.

I have an RLL and a SP1 RR. You only need a $3 pivot pin adapter to use small pin uppers with the SP1 lower - its pretty simple.

RLL is about 16k and RDIAS is about 35k depending on steel or aluminum. Both require tuning with the hosts.

RLL needs low shelf lower with relief cuts to prevent damage to the link (easily done) and bolt modification, then timing using paddles. There is good info on here around it.
You can modify a 3 round burst kit to have safe/semi/auto with RLL.

RDIAS won’t break as easy. Except maybe the paddle.
RLL can break easy because of material.

KNS protector has pretty much eliminated that issue on the rLL breaking, but naked its true.

Yes, I have broken my rLL.

Did it get better?

M60joe tonic cleared up that infection.

I’m guessing yours broke without the KNS protector installed?

Yes.  Now I know better.

Just curious, when it happened were you using a blow back setup like 9mm? Was the lower receiver relieved in the right places?

@steamedliver  Wow, sorry to hear about that.  Thank god M60Joe was still around at the time to fix it!

I'd also really like to know more specific details about your setup when it happened.  If you have pictures and dimensions of the lower receiver and pictures of the broken RLL, that would be great.  We all need to do what we can to share any knowledge on how to protect these gizmos.

Thanks,
Esox

Only because I absolutely respect you!  I am still using all the rLL accessories YOU modified.

What if I told you not a single lower was involved.  I’d only had it a month or so, alcohol was involved and a LOT of stupidity.  Let’s just say the metal is hardened, so its a brittle. I’ll take a picture of it.

But it did not break in a receiver, just from very aggressive handling.  And pliers.  And I wasn’t the only one involved.  We split the repair cost.

Ha!  'nuff said.  We ALL have stories like that!  ...and they are best left to only those who were involved and to take them to their grave.

dyyyiiinggg lol that sucks but soo glad to hear it got fixed.

Mine will hopefully be approved shortly depending on the govt shutdown stuff

Have not made a relief cut near the buffer tube but I'll see how close it gets when engaged

What’s a fair price right now for a RLL? Saw one sold for 14k on GB a few weeks ago...

damn, I got mine for 16 in May

@jt526

Do you have a picture RLL/ DIAS? I’m interested in seeing how it holds the auto sear.

Thank you