AR Rails without need for gas tube timing

[LanceCriminal]

From what I have seen, there are a few rail systems out there whose barrel nuts and rails can be installed without having to "time" the nut either to allowing the gas tube to pass through, or to allows screw holes on the rail and nut to align properly. I was wondering if there was a comprehensive list of which rail systems fall into this category?

The ones I can think of are:

Upcoming Geissele rail (which I really want)
http://www.weaponevolution.com/forum/showthread.php?3602-2012-Geissele

Templar Custom Fast Rail
http://templarcustom.com/products/railshandguards

Spike's/Seekins BAR and SAR rails (with the exception of certain Piston-drive kits)
http://www.weaponevolution.com/forum/showthread.php?3059-Spike-s-Tactical-SAR

From what I saw, the Templar and Geissele rails "should" allow one to more easily swap a barrel assembly for another fairly quickly, and possibly in less than "in your armory with all of your tools" conditions. By no means will I be running around "behind enemy lines" and have some need to be able to switch calibers to use enemy ammo, but I sure would love to be able to take both a 5.56 barrel and a 300 BLK barrel on a trip with some basic tools and be able to swap them out if I would like. While yes it would still need a bit more effort than say an ACR or SCAR, I feel it would still beat taking 2 separate rifles.

[markm]

I'd just take a second upper.

I don't get what issue there is with or without having to "time" the nut. There's a relatively wide torque +/- spec for a standard bbl nut.

This just strikes me as very silly.

[LanceCriminal]

That's true, I do already have a higher than 1/1 upper to lower relationship, and pushing out two pins is far simpler and quicker than changing a barrel. Not that it is 100% financially motivated, but we have oficially started on the path to having kids, so my financial priorities are going to shift away from buying every upper/rail/barrel combination I could ever want. Trust me, I'd rather just build an entire second rifle. My wife is totally onboard with me buying more gun bits, but if I can just buy another barrel, gas tube, gas block, and barrel nut (maybe a new bolt depending on caliber and headspacing) and have everything drop in and work, that would save me the cost of a second BCG, charging handle, reciever, rail system, rail covers, etc. That's more ammo I can buy to enjoy shooting the rifle, or extra cash to get a reloading setup going, or a new optic, etc.

And yes the torque specs are forgiving, but my brain always tells me things are off or crooked no matter I do. For example my PRI tube on my mk12 clone, no matter what I always felt it was always just a little off, either a little before or a little after the holes were perfectly aligned. Is it off enough to push the gas tube either way and cause cycling issues? Nope. The same applies to scopes/rings, clamp on FSB, etc. Even though a level, doing a plumb line, and other measureable devices might tell me that somethings is level or damned near to spot on, it always still looks crooked to me and I cannot leave well enough alone. I used to re-adjust the carpets in our barracks while I was on night shift to be parallel with the tiles on the floor, because it drove me nuts when I had to pretty much stare at them for 12 hours a night.

If there is an option where all I have to do is put nut on, torque to the same, consistent torque, I'd prefer that route. For me it is just personal preference. Same goes for the rail systems that don't have teeth but you need the barrel nut to align "just right" to mount the FF rails and have them on straight. I am neither an LEO, nor am I active MIL any longer, so all this is for the joy of building and shooting AR's.

Out of curiosity, why does the stock nut have the sprocket teeth? Are they there specifically to align or support the gas tube? To align the handguards?

[Stickman]

In this list you need to include the Daniel Defense LITE Rails as they were one of the first.

Are you looking to include rails which use an existing barrel nut which wouldn't need to be removed?

[LanceCriminal]

No, I'd be building this from the ground up. Do the RIS II Mk18 rails use the same interface as the DD Lite?

I'm also leaning towards the modular type rails like the NSR or Samson Evolution, but both seem to require you to align the nut. Again this is not a huge issue, but if easier and repeatable is available I'd prefer that. What I'm really psyched about is the Geissele rail, but it seems to be getting moved back more and more, and I've heard nothing about a 9" being available, just 13" and 15". I'd also go for a URXIII, but I haven't seen any in 9" length. Fortunately Robb Jensen is nearby so I wouldn't mind having him install it if a 9" were available.

[HeavyDuty]

I think the Wilson rail falls into this category, too.

[TripleBravo]

I think the Wilson rail falls into this category, too.

The Wilson Combat TRIM does require barrel nut timing, but not to provide clearance for the gas tube. Timing is easily achieved though, and shouldn't drive the OP away from considering it an option for a new build.

More details here: http://www.weaponevolution.com/forum/showthread.php?3182-Wilson-Combat-T.R.I.M.-Review&p=29851#post29851

[TripleBravo]

The Seekins BAR and SAR have different designs. The SAR does not require barrel nut timing, however the BAR does.

Again though, timing of the BAR barrel nut is achieved very easily utilizing the included barrel nut shims during installation.

[caporider]

DD RIS II barrel nut and locking screws are very similar to Lite Rail hardware. I prefer the RIS II for its lower profile and FDE option.

[LanceCriminal]

I spent a little time on the Youtube and found a vid showing how the DD Lite rail works. Looks like the barrel nut tightens, and the locking bracket thingy is allowed some play so you can align the gas tube. Guy then used an Aimpoint mount to align the upper and rail. The only thing for me is that I'd kind of like to have a modular rail vice a quad rail. All I really need to have is a grip and sling mount, maybe a light. At least the 6-8 month wait for my SBR stamp gives me plenty of time to save, ask questions, and fondle some of this stuff. This Black Rifle Disease sure is rough, It's gotten to the point that I have excel spreadsheets full of uppers I want to build, complete with pricing, links to products, weight, etc.

Stickman, have you heard any inside scoop from Noveske whether FSB or Switchblock compatible extended NSR rails are anywhere in the plans?

[LanceCriminal]

By the way, Geissele just announced on Facebook that the 13" and 15" rails are available by phone. Also mentioned were some scracth-n-dent ones for something like $30 off...