I've got most of the parts sitting around to do another build & frankly it'll be cheaper than going to the range.  I'm looking for a somewhat lightweight FF handguard.  

It'll be going on a 16" lightweight midlength barrel, and currently looking at the larue mlok handguard but I can't find any weights on it.   Everyting similar I'm looking at (midwest, centruion, etc) is about double the price.  I keep looking at ALG, but no idea when they'll be back in stock.

I just ordered this on a similar build:

https://www.midwestindustriesinc.com/MI-Ultra-Lightweight-One-Piece-Free-Float-Handguar-p/mi-ulw10.5.htm

@sscot  is it worth 2.5x the cost of the larue?  Though at 6.8 oz total it might be.     I had one of this but gen 3.  No complains except I missed having the full length top rail.

I will let you know what I think of it when it arrives. I have used several other Midwest rails and like them and even had a simple issue with (A very old one) one and Midwest sent me a fix for it for free. On my other I have a Spikes SAR and it is pretty light with Titanium nut and I like it a lot. I have not used the LaRue rail.

The LaRue rails are relatively heavy.  From what I was able to find, they're somewhere around 14-15oz. for the 12"-13" lengths.  Which isn't bad for a typical build - but you can definitely go lighter if that's your ultimate goal.  I have the older Midwest Industries Gen2 slim rails, and they're good.  I prefer the more solid mounting system for the ALG EMR rails (discontinued?) and was pleasantly surprised by the Aero Atlas rail -- although I haven't tried any of the newer Midwest rails to compare.  

Depending on your budget, the carbon fiber options from Brigand Arms, JAG, Smoke Composites, or Coda Evolution might be the lightest options you'll find.  You'll just have to play in the $200-300 price range instead of the $100-200 range.

My first build was intended to be fairly lightweight, and while it certainly isn't the lightest option (certainly also not the heaviest), I went with the Geissele Mk 16 and I'm pretty pleased with it, although I went with a shorter length than what most of y'all use for 16" rifles (10.5") for my own reasons (of which less weight was the least important).  With an empty 30-round magazine and two sling swivels installed, it weighs 6 lbs. 9.5 oz.  Without the magazine or swivels, it weighs 6 lbs. 4.5 oz.  I went with a pencil barrel, titanium lo-pro gas block, no-FA upper, and ALG swivels as part of trying to limit weight.  I had considered getting titanium parts for a number of the smaller parts, but I'd save only a little over 2 oz. at over $100 in cost, so I didn't bother with it  I also went with the LWRC compact stock so I could have the cheek rest of SOPMOD stocks but without the weight.  There are lighter options, of course, but these stocks aren't heavy.  For everything else, I just went with what I wanted without necessarily considering weight, but most of the major weight sources are already accounted for after the above.

@drewthebrave    Thanks for posting appox. weights, I couldn't find anything & it drives me nuts that Larue doesn't post specs on their website.  I'm not trying to go super lightweight just lightish.  If I had to guess the larue rails are heavier due to the barrel lockup mechanism.   The ALG EMR v3x is also a front runner since that should be fairly lightweight.  

This rifle will probably only have a holosun 403/503 & a light mounted on it so I just want to keep it fairly trim.

a light weight rail goes FAR as far as perceived weight goes. The weight on the end of a 16 inch lever isn't ideal for feeling light, it gets heavy quick. If you go for a lightweight build that weight being close to your shoulder makes a huge difeferance. (titanium flash hiders are great).

The BCM MCMR (and KMR if you don't mind keymod) are very lightweight. I also like the way their barrel nuts work.

I have a different brand that uses the same barrel nut system, the Bootleg PicMod. They also make an Mlok version.

The weak points in my lightweight builds are the optics and suppressors. Add a full magazine, and you can turn a six-pound rifle into a ten-pounder in a hurry.

@rodent   I’m not looking for super lightweight, just lightish.   My other rifles are running lpvo or long barrels.  I’m thinking to keep this build stripped down to a red dot and maybe a light.  It’s also a project bc I’m bored and ammo is expensive as hell.

I'm the same way, but you know what they say about good intentions...

Nothing is lighter than a red dot. Or faster. But, it's a 50-yard optic. Beyond that, magnification is necessary. If your state has antler restrictions, does that buck in the brush have three points or four? Is that dude holding a phone or a pistol? And besides, if the battery dies, you're done.

Prismatic scopes give you a little magnification at the cost of speed, but if you want a rifle that is capable of decently doing everything from 1 to 500 yards, you really need an LPVO. With a sturdy mount, that's close to two pounds. I think the optic is almost more important than the rifle, so I deal with it.

And then there's suppressors. I try to put them on almost everything. Nothing else eliminates flash, and I'm already half deaf, so...

Now that you have an accurate, do-everything rifle, how about a bipod?

What about a light?

Pretty soon I have a lightweight rifle I can hardly lift, with more controls than a 787.

@Rodent  Part of my logic here is a fairly light gun my wife can use at the range, or my boys can in a few years.  If the batties die I'll probably have cowitness irons since I've got a pair or 7 sitting around.  

I just can't find anything that seems as budgetish & lightish as the larue mlok rails.

I weighed my 13.2 Larue LAT:

14.8 oz with barrel nut & mounting hardware

11 oz bare rail

It's a great rail, especially for the price.

@ApocalypseMan   thanks man!  I think that seals the deal.  Time to order an 11" one.  I don't know why Larue can't publish weights like everyone else does.