Charlie and Delta.
http://troyind.com/rail-systemsaccessories/rails
I’m having hard time imaginig how they attach, but the description says they are two-piece rails and do not require removal of delta ring or FSB.
Pics
Charlie
Delta
I am interested as well. Also like to know the weight. The “Delta” rail in the Shot Show pictures doesn’t have the picatinny rail on the right and left sides like your pics and the ones on their site.
Very cool, I’m glad to see some more rails on the market with an FSP slot cut out. It’ll be interesting to see how the rail shapes up in the market.
Buddy of mine’s about to drop coin on a new 6920, and is looking for a way to add rails without changing out the FSP - I just sent him the links! 
they clamp on the the barrel nut, moving the D ring back…totally ff.
I could have sworn that I was shown one of these at shot without the rail. Did anyone else see that one or am I wishful remembering? Maybe im just remembering the delta, with the small portion of rail on the bottom
I bought the Troy MRF free float carbine rail system. I bought it from Botach for $152. I ordered black, and they sent FDE, so it’s going back. The installation appears to be the same as the Midwest 2 pc. FF rails. They are not difficult to install after you remove the delta ring and springs.
EDIT… My error. The Charlie and Delta rails have the Delta ring intact. But, I’ll bet it’s still a 2 peice set up.
Wonder what the specs are on that (weight, height, and length mostly). I’d be willing to accept some weight penalties for the luxury of not having to modify the gun.
Is it me, or does the portion in front of the FSB seem longer than what’s on the DD or Centurion versions?
ignore me…
I’m very interested in the Delta rail. A two piece FF rail that requires zero modification to the host gun, and extends past the FSB.
I called Troy yesterday about them. Couldn’t get any spec’s on it over the phone. I was told it’d 2-3 months before production on them is started though. Otherwise, I’d have one ordered.
My only concern is the mounting system. So long as there’s no play or twist, for lack of a better way of trying to explain.
When you go to the initial image on the Troy web site, the Delta and Charlie rails are the same photo. If you hit the Order button, then you see the correct photo for the Delta rail. The Delta doesn’t have permanently attached rails on the sides and bottom. It does have a short section of bottom rail under the FSB. You can attach pieces of rail where needed. This photo matches the description given for the Delta.
I looked good and hard at them, but for the weight of the Charlie system (which looked more attractive), I’d rather shell out the extra hundred dollars and just run the Centurion C4FSP rail with LT Index Clips and have the rifle done right now.
I really do like how the Delta version borrows some of the awesomeness from the TRX Extreme rails, but if you don’t plan on running a foregrip on that railed section, it’s a bit inconvenient.
That was the one I remembered B-trash.
Thanks
What impressed me was that you could mount a piece of rail, in front of the rail shown in the pic, and it would be continuous.
http://www.youtube.com/watch?v=0Ytd26TqWsA&feature=related
a video.
so
troy delta rail + colt 6720 = win?
I’m definitely interested in the Charlie rail. I was thinking about adding a bi-pod to my Colt 6920 but would like an extended rail system that allows me to have that and my VFG. I think the 7" rail I have is too short for both a VFG and bi-pod. I don’t want to modify the FSB either so I think this will be a great option for me. I can’t wait for Troy to release these new ones!
I’d say so…
I’m going to try and get a Delta rail as soon as they start shipping and try it on a 6920. I’m concerned about how solid the lockup is on the mounting system. Guess we’ll find out…
Very competitively-priced against the Daniel Defense Omega.
Troy needs to hurry and release a mid-length version of the Delta. 
Bit of a derail, but why did u pick 6920 over 6720?
Only because the 6720 did not exist when I bought my 6920’s.
Interesting indeed, now that $200 DD Omega X rails dried up. Looks like a solid lockup like the Centurion. What is key is the weight. Centurion is VERY light. Having more real estate on the front (as it appears) is good to mount the light fwd away from the FSP - then you can use bear handed if need be.
I can not find any info on what gas system Troy makes these new rails for. I can only assume the stupid carbine gas system on the 16" barrel.
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