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Link Posted: 11/12/2005 12:53:26 PM EDT
[Last Edit: draver] [#1]
I recently purchased a RDIAS which is now being transferred to my local dealer.

From my research, the DIAS is not caliber specific, but turns whatever platform it's installed in, into a sub machine gun.

Therefore, if you have a lower with it installed, the upper can be 9mm, .223 or whatever other cal. you have.  You will be within the requrements of the NFA, including barrel length less than 16".    If you own other AR's you might not want to have more than one short barrel, however.  Seems that there is a letter to that effect that specifies that you are in possession of a SBR if you have two short barrels, more than one lower,  and only one NFA tax stamp for either a SMG or SBR.

Here's the letter I am referring to, however, I do not claim it is the last word from BATFE.

www.cs.cmu.edu/afs/cs.cmu.edu/user/wbardwel/public/nfalist/atf_letter90.txt

Remember also that you don't just "Drop" a sear in and have a full auto gun.  You'll need the associated FCG parts as well as the sear, and my intention is to leave them installed in one dedicated lower, and switch uppers as I see fit.
Link Posted: 11/24/2005 5:48:27 PM EDT
[#2]
Does a Lighting Link work when the AR15 is not vertical?

Friend (who has half dozen HK sears and everthing else is chopped liver ;-) was thinking this is the case.

Paper work got messed up on the Lighting Link from this summer ... so still an option.
Link Posted: 12/20/2005 7:48:17 AM EDT
[Last Edit: joeblack] [#3]
Link Posted: 1/17/2006 4:27:10 PM EDT
[#4]

Originally Posted By JTinIN:
Does a Lighting Link work when the AR15 is not vertical?

Friend (who has half dozen HK sears and everthing else is chopped liver ;-) was thinking this is the case.

Paper work got messed up on the Lighting Link from this summer ... so still an option.



I assume you me horizontal. Yes the LL will work reguardless of orientation of the AR15.
Link Posted: 2/16/2006 1:44:23 AM EDT
[#5]

Originally Posted By tony_k:
If you get struck by lightning, or wander into a nuclear reactor unprotected, with either an RLL or RDIAS, they can be destroyed or contaminated beyond use. I only mention these possibilities because they are as likely to happen as you are to "blow up" an RR beyond repair.


I recall a tale of woe posted by someone on rec.guns many years ago.  His father had a house fire which totalled the house -- and melted his registered-receiver M16 into an aluminum puddle.

A steel RDIAS or RLL would probably have been unaffected, unless they're heat-treated or something.

Anyway, just a thought.
Link Posted: 2/18/2006 11:40:31 PM EDT
[#6]

Originally Posted By 71-Hour_Achmed:

Originally Posted By tony_k:
If you get struck by lightning, or wander into a nuclear reactor unprotected, with either an RLL or RDIAS, they can be destroyed or contaminated beyond use. I only mention these possibilities because they are as likely to happen as you are to "blow up" an RR beyond repair.


I recall a tale of woe posted by someone on rec.guns many years ago.  His father had a house fire which totalled the house -- and melted his registered-receiver M16 into an aluminum puddle.

A steel RDIAS or RLL would probably have been unaffected, unless they're heat-treated or something.

Anyway, just a thought.



yes but with that much money in a gun, its probably in a safe, a damned good one too.
Link Posted: 2/19/2006 11:01:13 AM EDT
[#7]
In a hot house fire the steel tends to be damaged due to heat (temper) plus small steel parts will tend to "burn" (i.e. form oxides).

Best policy is a good alarm system, fire proof safe and insurance if all goes bad.  A nice feature of the "small" NFA conversion devices, it that you can keep the "extra' ones in a bank box when not in use - and keep all the NFA coversion devices in the bank box during times of "no shooting" (winter up north, travel, holidays etc.).

Link Posted: 3/8/2006 12:30:18 PM EDT
[#8]
what are the associated costs with a RLL ?

I haven't been able to find any information of where you guys are legally purchasing these items. I've got about $20,000 budgeted, but obviously I'd like to spend as little as posssible to make room for other toys :)
Link Posted: 3/8/2006 12:59:38 PM EDT
[Last Edit: tony_k] [#9]
Link Posted: 6/8/2006 11:10:33 AM EDT
[#10]

Originally Posted By Quarterbore:

Originally Posted By Phil_A_Steen:

Others have challenged someone to cite an M16 kaboom  - no one has found one yet as far as I know.  Even if that does happen, a RR can be repaired.




One:  quarterbore.com/ar15m16/ar15kaboom2.htm Actualy two if you read the linked article...

Note:  Not that I would use one example to make up my own mind!  The bigger issue is that you will eventually wear out trigger pin holes.  Yes, they can be fixed but I would prefer to replace the lower with a new one by moving the sear or link to a new lower....



If you actually read the story, it clearly says the lower receiver was not damaged, the upper receiver was destroyed. Since the FA and clearly the most expensive part of a MG is the lower receiver, this story does not count as a minus against getting a lower receiver. Also, the story clearly said the cause of the stoppage and resulting kaboom was a lot of sand in the barrel, something I doubt many of us would allow.
Link Posted: 6/9/2006 8:15:56 PM EDT
[#11]
I remember in the 80's and early 90's the BATF's once-a-machinegun-always-a-machinegun rule married the rdias to the receiver once it was installed. You could install the rdias in any receiver, but once it was there that was it. I also believe the once-a-machinegun . . . rule was struck down in a case with Vollmer v. BATF by the DC Circuit in the early 90's. I never heard anything more on the subject since then. Did the BATF give up on enforcing the RDIAS -- Receiver marriage rule?

P.S. I just found this forum and I think it is great.
Link Posted: 9/7/2006 8:48:49 PM EDT
[#12]
As far as the DIAS being "married", before the 1981 change of ATF's machinegun definition, a guy could submit a Form 1 to convert his Colt SP1 to a machine gun.  Once approved he could go to a gunshow and buy a DIAS and the M16 parts.  Put them in his SP1 and have a funtioning sellect fire machine gun without having to drill the hole for the GI auto sear.  The unserialized DIAS is "married" to the SP1 receiver.  If on the other hand, he came up with a different serial # and registered the DIAS as a machine gun.  He could use the same set up but the DIAS would be listed as the machine gun with a physical decription of the sear as the machine gun instead of the description of the SP1.

As far as this debate of RLLvs RDIAS vs RR, I'm amazed no one has brought up the MGI system.  If you are unfirliar go to www.mgimilitary.com to see some pictures and specs.  In my opinion that is what has driven the price of a RDIAS past the price of a complete Colt M16.  MGI has a .308 slide on magwell and a .45 ACP gas operated upper with a magwell that uses unaltered Grease Gun mags.  They also have a beltfeeding modual in preproduction.  Slide off the GG magwell and slide on a 5.56X45 modual that will feed a standard M16 upper with 5.56 using SAW linked ammo.  All from the same lower.  Of course the beltfeed modual will only work with a MGI lower.  So you would need a RLL or RDIAS to convert the MGI lower into a machine gun.  To me a lower with a conversion device that will shoot .308, .45 ACP with unaltered GG mags, plus all the other calibers alread available to a M16, plus being capable of being belt feed, makes for a really cool machine gun.

Scott
Link Posted: 9/28/2006 1:08:22 AM EDT
[#13]
Can you use a RDIAS or RLL with an AR10 (.308 round)? Has it been done before?
Link Posted: 9/29/2006 3:47:20 PM EDT
[#14]

Originally Posted By Jason_R:
Can you use a RDIAS or RLL with an AR10 (.308 round)? Has it been done before?


I don't think so.  Quaterbore posted a pic of an AR10 DIAS (post sample) and it looked nothing like an RDIAS.  Also, Quaterbore was working on getting his RLL to work on an AR10, but I think that didn't work out as well.  Hopefully Quarterbore will step in here.  However, the MGI modular lower will have a .308 magwell and is compatible with an RDIAS and RLL.

Link Posted: 9/30/2006 1:07:18 AM EDT
[#15]
The MGI modular lower has a .308 magwell that is in development.  According to Mack at MGI, their .308 system will be full auto compatible.  So if you had a RDIAS in their .308 system it would be full auto.  Infact MGI has in developement a belt feed modual that will take the place of a magwell.  They are supposed to offer belt feed moduals in 5.56X45, 7.62X39, and 7.62X51.

Scott
Link Posted: 2/20/2007 11:53:51 AM EDT
[#16]

Originally Posted By canon3825:
The MGI modular lower has a .308 magwell that is in development.  According to Mack at MGI, their .308 system will be full auto compatible.  So if you had a RDIAS in their .308 system it would be full auto.  Infact MGI has in developement a belt feed modual that will take the place of a magwell.  They are supposed to offer belt feed moduals in 5.56X45, 7.62X39, and 7.62X51.

Scott


Also, the new POF .308 lower "looks" to be RDIAS and RLL compatible.

I got the impressiong from TWL that the .308 magwell is a while off from release since I the .45ACP and 9mm magwells are supposed to be released first.  And the belt fed uppers are a long ways off (probably years).  
Link Posted: 2/20/2007 1:39:03 PM EDT
[Last Edit: Quarterbore] [#17]

Originally Posted By nugentgl:

Originally Posted By Jason_R:
Can you use a RDIAS or RLL with an AR10 (.308 round)? Has it been done before?


I don't think so.  Quaterbore posted a pic of an AR10 DIAS (post sample) and it looked nothing like an RDIAS.  Also, Quaterbore was working on getting his RLL to work on an AR10, but I think that didn't work out as well.  Hopefully Quarterbore will step in here.  However, the MGI modular lower will have a .308 magwell and is compatible with an RDIAS and RLL.



Sorry, I never saw this post before now...

I actually never worked on the LL with the AR-10 much beyond seeing it would be possible.  All that it really needs is to have the shelf lowered a little and perhaps modify the rear takedown lug to allow clearance.  Then you would need to mill the bottom of the AR-10 carrier to work with the link but the basic geometry looks correct...

I still have photos and details uploaded here:

www.quarterbore.net/forums/showthread.php?t=167
and
www.quarterbore.net/forums/showthread.php?t=166

As for the DIAS, that will require quite a bit of work to ise with an AR-10 as the AR-10 rear takedown lug is larger.  To make this work with the DIAS you would need to weld the rear takedown pin hole closed, mill the rear lug down to the size of an AR-15 lug, and then redrill everything (at least I am pretty sure the AR-10 rear takedown pin is larger then an AR-15 and that there would not be a lot of meat left if you try to cut an AR-10 lug down to fit aroud the DIAS)

There is a SOT that makes a AR-10 LIGHTNING LINK that looks like a DIAS but when you look at it it is clearly a auto disconector and NOT a auto sear!

Details of this are posted here:

www.quarterbore.com/nfa/ar10autoconnector.html



Hope that helps some...
Link Posted: 3/29/2007 4:36:56 PM EDT
[#18]

Originally Posted By jtb33:
My understanding is that if I go with the RR or RDIAS, I'd have to get M16 bolt carriers for all the uppers I want to use with the NFA/C3 lower, and if I went with the RDIAS, in addition to bolt carriers, I'd have to get a fire control group for the lower I want to use the RDIAS in, and remove it when I remove the RDIAS, but the advantage is that I could use it in a *new* lower as long as it didn't have the sear block (shelf) in there.  The advantage of the RLL (as I understand it to be) is that I can use it in ANY AR15 without changing any parts and it will work fine; the disadvantage being that I lose the ability to use semi-auto while it's in there (unless I do some sort of modification to it).


Which companies make lowers without the shelf?



Originally Posted By joeblack:

Originally Posted By E22CAPT:
would it be possible to transfer the serial number from a sear that was distroyed to a new one by a manufacturer? <hr height=1px color=black noshade>

No, the serial numbers can not be transfered. You must repair the broken device.  Sear trips, pins, and springs are easy to make/get.


I'll accept this, but I'm curious where it's written in the BATFE "laws" that this can't be done.

Also, I thought I read in a way older thread about this being done before... or was it something else? Is there anything firearms related that can be re-manufactured and serial number transferred (with the old part being destroyed to avoid duplicates)? Or am I thinking of something like car parts of something completely unrelated?
Link Posted: 4/11/2007 1:08:05 AM EDT
[#19]

Originally Posted By pathfinder74:
Which companies make lowers without the shelf?


These lowers should be RDIAS and RLL friendly:
EARLY Colt
LAR foundry = LAR, Bushmaster, Ameetech (advertised as compatible), DPMS, CMMG (advertised as compatible), Double Star, Fulton
MMS foundry = Mega (advertised as compatible), GSE, Dalphon, POF, Alexander Arms
Bushmaster lowers without an "L" at the beginning of their serial number are made in-house by Bushmaster and are not DIAS compatible.  So says the internet folks, anyway.

There may be more lowers that are compatible, but those are the ones I'm told are safe.
Link Posted: 5/8/2007 11:25:34 AM EDT
[#20]
My RDIAS work fine in the POF P-416 Gen 2 receiver.  There is a littel more left and right play than normal, but it runs like a top!

Link Posted: 5/8/2007 12:51:22 PM EDT
[#21]
Link Posted: 7/26/2007 10:23:23 PM EDT
[Last Edit: iconted] [#22]
Sorry, Im kinda changing the subject, but where can you find a RDIAS and about how much do they cost.

ETA And can they be used in an unmodified lower receiver(except for fire control parts of course)
Link Posted: 2/26/2008 9:53:16 PM EDT
[#23]

Originally Posted By iconted:
Sorry, Im kinda changing the subject, but where can you find a RDIAS and about how much do they cost.

ETA And can they be used in an unmodified lower receiver(except for fire control parts of course)


saw one today for 13.5K  I would not sell mine for 15K.
Link Posted: 3/9/2008 12:46:51 PM EDT
[#24]
I may be wrong but a I don't think a LL won't work with POF bolt carriers.
I have a full auto carrier and a semi and the semi doesn't look like the pics of the SP1
carrier.
You could always mill it down if the specs aren't right.
Is anyone running a LL in a POF?
Link Posted: 3/28/2008 11:50:31 AM EDT
[#25]
pics??????
Link Posted: 3/28/2008 12:00:04 PM EDT
[#26]

Originally Posted By FloridaC3:
Apparently (I think one of the guys posting in this thread pointed it out in another) KNS Precision has made a new part to prevent link breakage.. This could really bump up the value of a link, as fragility was the key issue after the sleect fire kits were made..

Lightning Link - BEST buy in M16's..






do you have a link to the thread?
Link Posted: 3/28/2008 12:54:44 PM EDT
[#27]
Link Posted: 5/15/2008 8:05:24 PM EDT
[#28]
can you use a RDIAS in an ar10?
Link Posted: 5/15/2008 8:37:40 PM EDT
[#29]
Link Posted: 5/15/2008 11:07:31 PM EDT
[#30]

Originally Posted By tony_k:

Originally Posted By nl12:
can you use a RDIAS in an ar10?

Not legally, and not without modifications.


Why not legally?
Link Posted: 5/16/2008 11:00:17 AM EDT
[#31]
Link Posted: 6/5/2008 1:55:23 AM EDT
[#32]
What about putting an RDIAS in an AR15 which has an upper that's designed to fire 6.5 grendel or even a 9mm conversion?  Does it matter if you have to modify the bolt carrier for timing or function, assuming it's necessary?
Link Posted: 6/5/2008 6:51:36 AM EDT
[#33]
Link Posted: 6/5/2008 1:18:39 PM EDT
[#34]
SWEET!... for now....
Link Posted: 8/19/2008 11:59:20 AM EDT
[#35]

Originally Posted By tony_k:

Originally Posted By VelveteenMole:
What about putting an RDIAS in an AR15 which has an upper that's designed to fire 6.5 grendel or even a 9mm conversion?  Does it matter if you have to modify the bolt carrier for timing or function, assuming it's necessary?

Uppers in different calibers or that require tuning for timing aren't a problem: As long as they bolt onto a standard-spec AR15 lower receiver, you are good to go with an RDIAS. At least, they are OK today -- who knows what BATFE will rule tomorrow?


The new Magpul masada Bushmaster ACR uses an AR15 lower reciever. They even claim that you can use the same trigger packs for the new rifle. Does that mean you can put an AR15 RDIAS in it legally?
Link Posted: 10/7/2008 3:20:24 PM EDT
[#36]
Could someone explain the process for putting a new upper on each of these (a RR, a lower with a RDIAS installed, and a lower with a RLL in it)?  I'm just wondering what all is involved with swapping from .223 to .22LR or 9mm or some other caliber on each of these.

-Nick
Link Posted: 10/7/2008 5:32:46 PM EDT
[#37]

Originally Posted By Etnomaiab:
Could someone explain the process for putting a new upper on each of these (a RR, a lower with a RDIAS installed, and a lower with a RLL in it)?  I'm just wondering what all is involved with swapping from .223 to .22LR or 9mm or some other caliber on each of these.

-Nick

Typically, with a RLL or RDIAS, we have several hosts.  

I have 4 AR's in different configurations and all I have to do is remove the RLL from the current host, and throw it in the new host.  It's that easy.  I may need to swap paddles on the LL if required for timing.  When I get a new host, I measure and then order custom paddles for that specific rifle.

With a RDIAS, you have to use a M16 FCG.  You'd have to remove the RDIAS from the current host and remove the FCG.  install the FCG in a new host along with the RDIAS.  If you're just going to use a new upper receiver, all you'd need to do is swap the upper and that should be it.  I'm not too sure as I don't have a RDIAS.  There may or may not be any timing issues.

With a RR it's a bit different.  You'd have to add a mag block if it's required for a sub-caliber.  One of my buddies has a RR and he has a light hammer spring for .22lr use.  If he's going to shoot any other caliber, he has to swap that spring out.  

IMO the RLL is the conversion device.  
Link Posted: 10/8/2008 11:16:42 AM EDT
[#38]
height=8
Originally Posted By Magoo6541:
If you're just going to use a new upper receiver, all you'd need to do is swap the upper and that should be it.  I'm not too sure as I don't have a RDIAS.  There may or may not be any timing issues.


Does anyone know the answer to this?  I am thinking about going the RDIAS route sometime in the distant future and will probable keep it in one lower most of the time.  If I do this, will I need to do a bunch of adjustments/check timing/etc. every time I swap from a .223 to a .22LR upper?

Also, from looking at pictures (posted in the latest F/A picture thread), I see some lowers marked for 3-round burst AND auto (along with safe and semi).  I've always though it was just one or the other.  How does this work?  Can it be done with a RDIAS?  (I probably sound like an idiot asking this question, but ya gotta find out somehow, right?)

Also, again so I don't sound like an idiot in the future, is an AR15 with a RDIAS installed still called an AR15, or is it then an M16?  Or are only Colt M16s called M16s?
Link Posted: 10/8/2008 12:29:08 PM EDT
[#39]

Originally Posted By Etnomaiab:

Originally Posted By Magoo6541:
If you're just going to use a new upper receiver, all you'd need to do is swap the upper and that should be it.  I'm not too sure as I don't have a RDIAS.  There may or may not be any timing issues.


Does anyone know the answer to this?  I am thinking about going the RDIAS route sometime in the distant future and will probable keep it in one lower most of the time.  If I do this, will I need to do a bunch of adjustments/check timing/etc. every time I swap from a .223 to a .22LR upper?

Also, from looking at pictures (posted in the latest F/A picture thread), I see some lowers marked for 3-round burst AND auto (along with safe and semi).  I've always though it was just one or the other.  How does this work?  Can it be done with a RDIAS?  (I probably sound like an idiot asking this question, but ya gotta find out somehow, right?)  

It will work with a RDIAS.  I'm not sure how it works.  From what I've read on here, it's extremly complicated and most people switch back to a standard FCG

Also, again so I don't sound like an idiot in the future, is an AR15 with a RDIAS installed still called an AR15, or is it then an M16?  Or are only Colt M16s called M16s?

It's still an AR-15.  Even converted RRs are referred as a AR-15 RR.  The only true M16's are those that left the factory as a M16.  Look at an ad for a 601.  Still an AR-15 601.

When asked about my AR's I will typically tell them it's an M16 and if they are interested, I'll explain that it's just an AR with a RLL.  It just makes it simplier as people tent to associate full auto AR's with the M16.
Link Posted: 10/8/2008 6:57:22 PM EDT
[#40]

Originally Posted By Etnomaiab:
Also, from looking at pictures (posted in the latest F/A picture thread), I see some lowers marked for 3-round burst AND auto (along with safe and semi).  I've always though it was just one or the other.  How does this work?


As your other questions were answered already, I'll just address this one.  The 3rd burst kit works by having two disconnectors, a regular one, and the burst disconnector, which is actuated by the burst cam on the modified 3rd burst hammer.  In semi, both disconnectors work together, and the function of the burst disconnector is redundant, since the regular disconnector is functioning on every shot.  In burst, the selector cams down on the tail of the regular disconnector, preventing it from engaging the hammer.  The burst disconnector has no tail to engage the selector, so its function is regulated by the notches on the burst cam.  The burst cam holds the burst disconnector out of engagement with the hammer for two shots, then lets the burst disconnector grab the hammer after the third shot.

The "enhanced" or "4-position" kit is the same as a 3rd burst kit, but BOTH the disconnector and burst disconnector have "tails".  In "semi" neither disconnector is held back by the selector, so the regular disconnector does it job of grabbing the hammer after every shot.  In "burst", the regular disconnector is held back by the selector, but the burst disconnector is allowed to do its job of grabbing the hammer on every third shot.  In "auto", both disconnectors are held back by the selector, allowing fully automatic fire.
Link Posted: 11/20/2008 1:47:32 PM EDT
[Last Edit: Suburban] [#41]
Link Posted: 11/12/2010 10:14:15 PM EDT
[#42]
Dumb question, but would someone tell me what an FCG is. Thanks
Link Posted: 11/12/2010 11:09:34 PM EDT
[Last Edit: Circuits] [#43]
Originally Posted By rico903:
Dumb question, but would someone tell me what an FCG is. Thanks


Fire Control Group

Consists of:  hammer, hammer spring, hammer pin, trigger, trigger spring, trigger pin, disconnector, disconnector spring, selector, selector detent, selector detent spring

full auto adds: auto sear, auto sear spring, auto sear pin and the hammer, trigger, disconnector and selector are slightly different
3rb adds:  burst disconnector, burst disconnector spring, burst cam, burst cam spring, with the hammer, trigger and disconnector again being slightly different.
Link Posted: 3/11/2017 1:04:45 PM EDT
[Last Edit: Johnson184] [#44]
Gotta clarify something.
With a RDIAS, a person can use a 300BLK,9mm, .22LR, etc upper without issue...
can a person do the same with a Colt M16A1 lower that's marked .223 or 5.56?
Link Posted: 3/11/2017 2:53:37 PM EDT
[#45]
Link Posted: 3/11/2017 7:10:33 PM EDT
[#46]
Link Posted: 4/5/2017 7:25:53 PM EDT
[#47]
Link Posted: 1/16/2020 10:54:08 AM EDT
[#48]
I can't decide if I want to laugh or cry looking at some of the prices that were quoted at the beginning of this thread
Link Posted: 1/16/2020 11:38:49 AM EDT
[#49]
Discussion ForumsJump to Quoted PostQuote History
Originally Posted By colossians323:
I can't decide if I want to laugh or cry looking at some of the prices that were quoted at the beginning of this thread
View Quote
And I'm sure people considered those prices "Outragous" back then just like they do now. 20 years from now people will look back on $18k for a non-colt RR and wish they would have bought when they were "Cheap"
Link Posted: 1/12/2022 8:36:37 PM EDT
[#50]
Discussion ForumsJump to Quoted PostQuote History
Originally Posted By Spartikis:


And I'm sure people considered those prices "Outragous" back then just like they do now. 20 years from now people will look back on $18k for a non-colt RR and wish they would have bought when they were "Cheap"
View Quote View All Quotes
View All Quotes
Discussion ForumsJump to Quoted PostQuote History
Originally Posted By Spartikis:
Originally Posted By colossians323:
I can't decide if I want to laugh or cry looking at some of the prices that were quoted at the beginning of this thread


And I'm sure people considered those prices "Outragous" back then just like they do now. 20 years from now people will look back on $18k for a non-colt RR and wish they would have bought when they were "Cheap"


Lolol.  20 years?  Try 2....here we are.
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