Building a sub 6lbs AR-15 and need help choosing an upper

[Goofball310]

 I have the parts chosen for my next build but I'm having a hard time finding a regular USGI upper receiver without forward assist. I've narrowed the build down between a regular USGI mil-spec upper and a Vltor MUR-1S without forward assist. If anyone has any info regarding their weight I would greatly appreciate it. Every ounce counts on this particular build. I might even consider a USGI upper with forward assist block. Here's my current build sheet:

 

 

CHEELY CUSTOM TITANIUM COMPENSATOR

JP LMOS BOLT CARRIER

MAG TACTICAL LOWER RECEIVER

JP LMOS BUFFER JP TUNED AND POLISHED SPING

STAG LOWER PARTS KIT

MAGPUL MOE-K PISTOL GRIP

ACE SKELETON STOCK

NOVESKE 11" NSR

14.5" DANIEL DEFENSE MID-LENGTH LIGHTWEIGHT BARREL

PRI LOW PROFILE GAS BLOCK

VLTOR BCM CHARGING HANDLE

WMD GAS TUBE

MAGPUL MBUS FRONT & REAR SIGHT

ALG COMBAT TRIGGER

 

 

 

Edited April 18, 2013 by Goofball310

[98Z5V]

If you go with the old, proven Cav Arms lower, it's a pound lighter than a comparably built aluminum lower.  Cav Arms isn't producing them anymore, but a newer company picked up the rights, and has them in production again.  I'd start there, first and foremost, on a sub-6lb build.  That's an easy pound of it, right there.

 

http://www.gwacsarmory.com/lower-receivers-1/

Edited April 19, 2013 by 98Z5V

[Goofball310]

I already bought the Mag Tactical lower and got it for a decent price on GB. Dixie Ammo has their auctions starting at $145 and no one seems to be bidding on them and Brownells has them on their site for $220.

[98Z5V]

You can always use that for something else...  I'm just sayin'...