Thought I would add some data. Relatively new to the LR-308 platform. I got a 3rd hand custom DPMS with a SASS barrel and CF forearm that shoots old mil surp ammo way better than anything should, but that SOB is heavy with no provision for a front sight that's needed for 3-gun Heavy Metal(or He Man) division.
Here's what I used for my build. Didn't come in quite a svelte as the previous one mentioned:
Part Weight(oz) Description
Upper 14.2 DPMS .308 A3 Receiver (Stripped), Part Number 308-FTT-EA
BCG 17.55 APF Armory Bolt Carrier LR-308 Nickel Boron, APF Armory Bolt Assembly LR-308 Nickel Boron
- comp kit 0.8 DPMS - 308AR BOLT COMPLETION PACK(Firing Pin, Cam pin, Retaining Pin)
CH 1.3 Bravo Company / Vltor 7.62mm 308 Mod 4 Charging Handle
Barrel 38.3 Rainier Arms Match™ .308 Barrel - 16 (ODS); Stainless Steel Match Grade Blank
Gas Block 1.55 Low Profile Adjustable Gas Block Set Screw Mount .750 Mil-Spec 556 nitrided
Gas Tube 0.7 Spikes Tactical - Melonite-Coated Gas Tube, Mid-Length
Handguard 13.7 Samson Evolution Series Customizable Free Float Handguard DPMS LR-308 with Low Profile Upper Receiver Aluminum Black
Sight - F 1.3 SAMSON MANUFACTURING CORP - AR-15/M16 FIXED FRONT SIGHT
Sight - R 1.55 SAMSON MANUFACTURING CORP - AR-15/M16 FIXED REAR SIGHT
Comp 3.85 Fortis Compensator RED™ 308 w/ crush washer
Even though this adds up to 94.8 oz, the completed build comes up as a weighted 95.1(5.9 lbs) - so obviously some rounding errors. That's a little over 2 lbs lighter than the 18" bull barreled SASS scoped upper.
With the lower I'm at 8.7 lbs. Looks like I can trim a little weight if I go from my full A2 stock to a collapsible - which I may do.
No comments about how the comp is installed upside down. I realized it just as I was tightening it down and then broke my fixture as I was attempting to take it back off.