View Full Version : DD Lite rail 10.0 install and observations

1 May 2009, 07:47
First off, this is my first personally owned AR-15. I'm very familiar with the rifle however from my father owning and building them, to my military time with the M16 and M203. For various reasons, I recently took the plunge and picked up my own, and through reading and research have learned a ton.

After finally getting everything in little boxes laid out in the den floor, I tackled the Lite rail install yesterday afternoon and have a few observations I wanted to note. The receiver block I'm using is the DPMS block. When pinned both front and rear, the DD bolt up plate did not want to turn freely when tightening the nut. Probably something I can fix on the block by sanding the two curved edged down a bit but nothing major. Second, the DD wrench I picked up from Midway (along with the receiver block and DPMS multi wrench) did not quite fit the DD barrel nut. It appeared it was somewhat "out of round" with the nut, and would not allow all teeth to engage. I managed to snug it up enough to attempt to tourque it, but became concerned with the fit of the wrench to the nut to not attempt it. What I did find, however, was that the DPMS spanner for the stock castle nut did fit the barrel nut perfectly even though there was only one tooth. This allowed me to torque the barrel down to 65 lbs. Not knowing exactly what "spec" should be (insert whatever fault here, I can remedy the amount of torque) I picked a happy medium between DD's recommended 50-75 lbs. Passed functions check and test firing and will be zeroing it today in the back yard.

I definitely don't want this taken as a gripe about DD wrenches or quality or whatever. I am absolutely pleased. I had previously read a thread regarding a similar experience elsewhere about the teeth on the wrench being an issue, and I was pleased to find that the DPMS multi wrench allowed me to finish up. I do not condone it to be an 'end all' solution in any way, 3 tooth engagement is way better than 1, but it worked for me without damaging the nut or wrench. I am going to give DD a shout today to let them know about the wrench and see if there have been other issues, but most assuredly will not fuss at them.

I would love to hear if anyone has run into any hiccups in an install similar to this. Just be aware at least for me, the DPMS receiver block didn't like the DD install.

Pardon the quick phone cam shot please, I'll attempt some better shots today in good daylight:

Armalite M15, 16" 1/9 midlength. DD Lite 10.0, Larue low profile gasblock (dimpled barrel), Larue UDE kit - Magpul CTR, MOE grip, XT panels, Foward grip, Magpul trigger guard (something I really liked and noticed when installed BTW), Magpul MBUS front and rear, PWS FSC556 (which was a PITA to install due to bottoming out prior to touching the peel washer on this particular barrel). I'm holding out on any optics until I see feedback on the IOR Valada 'Pitbull' 1x/4x.


4 May 2009, 16:14
Good job on the install, but I have a question. I have a Panther Claw block as well. When I installed a Lite rail, I ran into the issue with the bolt-up plate as well. I dremelled down the blcok so that the plate would fit and rotate. I found that the barrel nut was nut snug all the way down. Did you insure that your barrel nut was completely tightened?

Also, the barrel nut and castle nut are very similar. I have heard that you can easily modify a stock wrench to fit the DD barrel nut. Perhaps DD has made a change in the barrel nut?

John Hwang
4 May 2009, 17:16
The barrel nuts are total different so you will need the proprietary barrel nut wrench or get a adjustable spanner wrench. I use a spanner wrench for many of the applications that need a barrel nut installed.

5 May 2009, 18:00
Beavo - I did the same except I simply used a flat file to the DPMS block. I had the same concern that I may have thought it was snug at first, backed it off and retourqed it.

John - I agree, if you're doing various installs with different type nuts the adjustable is ideal. I was relatively pleased that the multi wrench was able to properly finish the job up.

5 May 2009, 18:56
Where the hell are the pictures?

5 May 2009, 20:25
Hmm, apparently my old photo hosting site went TU...

Here's a fuzzy shot of the block trying to point out the problem area. There's two dimples in this area that I filed down to fix the problem mating up the DD bolt up plate. (Coffee and one handed pics don't mix...)


I've put a couple of mags through it since the build and it's holding zero with respectable groups for me, what I may do is disassemble the rail, bolt it back up to the block and take a few better shots of it in the vise (and re-check the tourque while at it).

Finished result -


5 May 2009, 21:36
Ok, out of sheer boredom I went ahead and pulled it to check and be sure. TQ is dead on.

A shot in the vise. The original interference was only at the two lower bolt holes on either side, the rest cleared:


and bolting the rail back up :

I'll get out tomorrow and verify the zero again to be sure I didn't bugger anything up tonight.

on edit, yup, I know my photos inhale with great vigor....

8 May 2009, 11:45
Question on the Lite Rail install, hopefully John Hwang from Rainier can chime in. Is it necessary to remove the gas block when installing? The reason I ask is, I wanted to purchase the Noveske 14.5" Afghan barrel and have Rainier perm attach a Vortex flash hider onto it for me (do you offer this service btw?). And then I can install a Lite Rail 12.0 myself.

When researching the Daniel Defense Lite Rail, I came across this vendor whose product description says removing the gas block is not needed:


However, I am not sure if this is true for just the Lite Rails that Global Tactical stocks or if all vendors have the same version. It would be great to know if Rainier has everything I need as they have treated me well in the past and I would like to keep my business there.

Thanks in advance

8 May 2009, 16:19
Not John here in any way, but to get the barrel nut and bolt up plate on, you'll have to remove the gas block. The actual rail piece itself will just go over at least a Larue low profile block, I couldn't say on any others (but I think it would). Maybe the ad isn't quite clear, and I understand what you're seeing:

The Lite rails that are now in stock are the newest version that allow you to install the gas block and gas tube prior to installation of the rail. This just the improvement the Lite Rails needed.

After pulling the rail section again after install for the above pics, I think that's what they're getting at in the quoted statement, the rail section itself.

8 May 2009, 16:55
Ok, I think I understand a bit better now, thanks. It seems that I will have to remove the gas block anyways. I guess the newer version of the Lite Rail is designed so that it is easier to install the gas block before actually putting on the rail. I suppose I should have the flash hider pinned/welded after I at least put on the barrel nut and bolt plate.

8 May 2009, 16:59
Actually I now have a different but related question. Will the barrel nut and bolt plate fit over a permanently attached flash hider? I just ordered the Noveske 14.5 barrel and Vortex from Rainier because I was afraid they would go out of stock. If the barrel nut will fit over the Vortex, I'd like to have Rainier pin/weld it for me if they can.

8 May 2009, 17:09
Using the old barrel nut as a guide, it will fit over both the FSC556 compensator and the A2 birdcage I have. However, the issue you'll run into is the gas block will not install over the Vortex, so pinning the Vortex is still going to have to happen after install of the plate, nut and gas block.

8 May 2009, 19:03
You're totally right, I had a major brain fart back there :o
I think I was assuming I could slide the barrel nut on from the chamber end before inserting the barrel into the upper receiver.

Jerry R
8 May 2009, 19:37
Nicely done Son, and a good write-up.

8 May 2009, 20:20
Well thanks! Too bad you weren't around to take better pics for me...LOL

8 May 2009, 20:53
I agree, and as a side note, I really enjoy that shot of your 10.5...

If I'm to build another, It'll have a DD Lite rail, period.

20 May 2009, 11:22
The receiver block I'm using is the DPMS block. When pinned both front and rear, the DD bolt up plate did not want to turn freely when tightening the nut.I'm having a little problem understanding how this rail locks up. If the bolt up plate can spin freely after the barrel nut is tight, what keeps the rail from rotating after it's bolted to the plate?


20 May 2009, 12:46
Best way that I can explain is this:

The bolt plate is behind the barrel nut, the rail is in front. When you're tightening the rail to the bolt plate, you're basically tightening the entire unit against the barrel nut, which prevents it from turning after alignment.

20 May 2009, 13:14

That's kind of what I was guessing. I'm a little leery that torque applied to the rail might eventualy cause the barrel nut to move, but since I haven't heard of any problems with this setup, I suppose I'm just a little paranoid.


20 May 2009, 20:48
I know this thread is about a different DD system than I have, but I wanted to toss in a gripe of my own about my Omega Rail, since the type of bolts DD uses was being brought up. On my rail, there are 4 bolts, two on each side, that hold the upper and lower halves together. These bolts seem to be made of some very soft metal, as I was able to semi-strip out the flathead slots on top with very little effort. I am not an incredibly strong guy, nor am I one of the types that torques things down until they all but break. Even though this does not effect the functioning of the handguard, I felt a little put off by spending $260 on a handguard and getting what I felt like were cheap bolts.

4 June 2009, 19:33
Those SCREWS in the Omega rail are horrible. I always replace them with stainless steel flat socket cap screws. They are good enough if you have the proper tools to install them. It sounds to me like you had a flat head screwdriver that was too small for the job. I would not blame DD for your error. I've installed 2 of these rails without stripping those screws but I MUCH prefer socket head cap screws. People balk at them because not every armorer's tool kit will have the right size allen wrench, but I use blue loc-tite on the screws to keep them in place as well as using the plastic washer.

ScottHM, if you can put enough torque on that rail to exceed 65 ft-lbs and move the barrel nut, you've got to have gorilla sized forearms! Seriously, the lock up system is very, very solid when installed properly. I've run a 14" and a 12" Lite and tried to get them to rotate and cannot do it by hand even with a VFG. I just cant generate enough torque without hurting myself.

4 June 2009, 19:52
Those SCREWS in the Omega rail are horrible. I always replace them with stainless steel flat socket cap screws. They are good enough if you have the proper tools to install them.

I like that idea, I've found them soft as well.

ETA- Spamsammich, welcome to the board, its good to see you over here.

5 June 2009, 06:42
Thanks for the welcome Stickman! It's good to be here. If you are having trouble with the screws you can get some from McMaster-carr for real cheap. If you don't like the shiny 18-8 stainless you can get these


They are black oxide coated and they have a nylon self locking plug in the threads. I believe the ones I used last time were 10-32 x 3/8.

If that's not your cup of tea, bring one of the screws to Sears and get a driver that fits in there nice and snug and is as close to full width as possible. I borrowed one from our metal shop and I've never stripped them out. If you use loc-tite or some other sort of thread lock, they don't really take much torque to secure the rail. Because of the size of the screw head we tend to thing we really have to bear down on it, but that's not the case.