*** LAST UPDATE 12/14/2020 ***
I thought I would make a post or series of posts concerning the weights of individual parts. If there is enough interest, this can be a living, breathing list with new products added. This is intended to help people who want to build lightweight rifles and/or want to lighten up an existing rifle. This is not necessarily intended to be a comprehensive list, as I won't be adding a lot of "heavy" parts- there isn't a point for that here.
RAW DATA SPREADSHEET HERE, v1.03

An updated Parts Database made by another user is here:  
Check this Google Doc
It may be more complete / more updated.

My recommended cheap / light build if you only want to get under 6lbs for under $1k ish.


I am also working on posting a spreadsheet containing all the raw data for this post. The great thing about a spreadsheet is, you can modify it and create a virtual list of parts that will help you determine what your rifle might weigh before you spend a nickel.

Please do not post in here if you don't like lightweight parts, don't like lightweight rifles, or have nothing useful to contribute related to the topic at hand.

Key:
U = User Data
M = Manufacturer
C = Calculated

Weights listed are in ounces.

Parts in purple are amongst the lightest options


****Upper Parts****
Muzzle Devices
A2 Flash Hider       2.15 U
A2 Extended
Mag Tactical             1.90 M
BE Meyers               2.50 M
AAC Brakeout 51t   4.20 M
AAC Blackout 51t   4.30 M
VDI Manimal            1.48 M
Rainier Mini-Comp    1.44 U
ALG Single Chamber Brake 2.01 U
V7 Titanium   1.35 M
V7 Ti V-grooved  1.25 M
Venom Defense hybrid steel muzzle brake 1.48 U

Charging Handles
PSA Milspec  1.13 U
Spikes Milspec 1.07 U
Rainier Raptor 1.42 U
BCM Gunfighter Med   1.24 U
BCM Gunfighter Small

Bolt Carrier Groups
LMT Semi-Auto 11.14 U
Umbrella Corp Full-Auto 11.46 U
RRA Semi-Auto 11.26 U
Spikes NIB FA 11.8 U
Colt F/A BCG 11.56 U
BCM F/A BCG 11.64 U
PSA F/A BCG 11.50 U
Red X Arms Ti 7.81 M
JP LMOS Bolt Carrier 6.25 M
JP Bolt Carrier (full mass) 8.5 M
Young Man. SLC carrier   7.1 U
FN Bolt Only 1.5 U
Smith Aluminum carrier w/ key 3.7 U
PM&T Ti carrier w/ key 5.1 U
V7 Systems Ti Carrier  5.7 M
V7 Systems Ti BCG  7.9 M

Gas Blocks
BCM 0.75"  1.30 U
BCM 0.625" 1.928 U
Daniel Def LPGB 0.750        1.28 M
Daniel Def LPGB 0.625        1.92 M
Daniel Def FSB 0.750           5.02 M
Daniel Def FSB 0.625           5.54 M
V7 Systems Ti LPGB 0.750  0.74 M
V7 Systems Ti LPGB 0.625  0.71 M
2A Armament Ti 0.750   0.70 M
VLTOR 0.625" (set screw)  1.4 M
Parallax Tactical LPGB          1.47 U
YHM LP w/ set screws 1.43 U

Gas Tubes
Del-ton Carbine 0.63 U
Carbine Length  0.7 C
BCM Midlength 0.757 U
V7 Midlength 0.94 U
Mid Length  0.8 U
Rifle Length 0.9 U

Misc
Dust Cover Assembly  0.75 U
Dust Cover Ass., V7   0.37 M
Mako Poly Dust Cover: 0.2 UBCM Dust Cover 0.506 U
BCM Dust Cover Pin 0.211 U
BCM Dust Cover Spring 0.021 U
BCM Forward Assist 0.712 U
BCM FA Spring 0.058 U
WOA Forward Assist Assy  0.74 U
Northtech Ti Forward Assist 0.501 U
Northtech Ti FA Spring 0.050 U
Schuster Mfg FA plug  0.10 U

Upper Receivers
2A Armament Balios Lite stripped, no FA  5.8 M
Aero Precision Forged Stripped 7.16 U
Aero Precision Forged Stripped; no FA   6.50 U
Kaiser US X-7 Fusion Upper:  5.2 M
Kaiser X-7 Poly Upper: 5.9 M
Mega Arms forged stripped 6.9 M
Mega Arms Billet Upper, 9.4 M
Forged Stripped, slickside
Rainier Forged, Complete  8.6 M
Rainier Arms Forged Stripped 7.08 U
Spikes Forged complete: 8.4 U
V7 Weapon Systems Forged Complete 7.7 M
V7 Weapon Systems Forged stripped 6.8 M
V7 Weapon Systems Enlightened 6.0 M
Forged no FA, complete  7.3 C
Mag Tactical Upper, stripped  4.8 M

Barrels
Note: All "government" profile builds should have 0.750" gas block seat

Bravo Company Machining
16" BFH Carb Lightweight 23.8 U
16" Mid Lightweight 24 M
16" M4 Carbine 28 M
16" Standard Mid 28 M
16" Standard BFH Mid 28 M

Daniel Defense
14.5" DD Mid gov't 0.750 24.5 U
14.5" DD Mid lightweight 22.0 C
14.5" DD Carb Lightweight 20.5 M
16" DD Light Mid, 0.625 21.2 M
16" DD Light Mid, 0.625 24.7 M
16" DD Govt Mid, 0.750 27.07 M

Faxon Firearms
14.5" Pencil Barrel Mid  17.5 M
16.0" Pencil Barrel Mid  19.1 M

Spikes Tactical
14.5" Spikes LW Mid 22.0 M
14.5" Spikes ST-FN mid 24.4 M
16" Spikes m4 LE Mid 27.9 M
16" Spikes ST-FN CHF mid 26.4 M
16" Spikes m4 LE carb 28.0 M

VooDoo Innovations
14.5" VDI Ultra Lt Mid 0.625  22.0 M
14.5" VDI gov't mid 0.750  24.3        M
16" VDI Evo Ultra Lt Mid 0.625  23.25 M
16" VDI Evo Ultra Lt Carb 0.625  23.25 M
16" VDI gov't mid 0.750        27.17 M
16" VDI gov't Carb 0.750         27.5 M
16.5" VDI/Adams UL Rifle 0.750  21.14 M

Free-float Handguards / Rails (weight includes Barrel Nut / Mounting Hardware unless noted)

Mil-Spec Barrel Nut  1.29 U
V7 Titanium B Nut   0.78 U

Bravo Company Machining
BCM KMR10  6.3 M
BCM KMR10 w/ barrel nut 8.6 M
BCM KMR13  7.7 M
BCM KMR13 w/ barrel nut 10.2 M
BCM MCMR8 w/ barrel nut: 7.6 M
BCM MCMR10 w/ barrel nut: 8.9 M
BCM MCMR13 w/ barrel nut: 10.5 M

Centurion CMR 12" 10.7 M
Centurion CMR 14" 14.2 U

Clark Carbon Fiber
Clark 9" 5.0 M
Clark 12.7" 6.0 M
Clark 16" 7 M

Fortis Manufacturing
Rev Carbine Cutout 7.9 No Barrel Nut
9" Rev Carbine 7.9 No Barrel Nut
Rev Mid Cutout 9.2 No Barrel Nut
12" Rev 9.2 No Barrel Nut
14" Rev 11 No Barrel Nut

Guntech M-LOK rails.
Anything 9" and under (9", 7", 4") now use steel barrel nuts. 10" and up (10", 12", 15") use lighter aluminum barrel nuts.

10" - 7.78
12" - 8.98
15" - 10.58
Weights include the 6x steel screws

12.5" Odin Works Keymod 10.15 M

Midwest Industries
10.5" ULW  6.8 M
12.63" ULW 7.9 M
10.5" SSK 7.74 U
12" SSK 8.6 U
15" SSK 9.9 M
7" SS Gen2  7.1 M
9" SS Gen 2  8.3 M
10" SS Gen 2  8.6 M
12" SS Gen 2  9.3 M
15" SS Gen 2  10.9 M

Noveske
11" Noveske NSR 9.8 M
13.5" Noveske NSR 11 M
15.0" Noveske NSR 11.6 M

Samson Manufacturing
10" Samson Evolution 9.8 M
11" Samson Evolution10.5 M
12.4" Samson Evo 11.5 M

Seekins Precision
9" Seekins MCSR V2 8.4 M
10" Seekins MCSR v2 9.1 M
12" Seekins MCSR V2 10.5 M
12" Seekins SP3R mod
14" Seekins SP3R mod

SLR Rifle Works
15" SLR Solo 3-gun 10.2 M
13" SLR Solo 3-gun 9.0 M
15" SLR Solo Light 11.4 M
13" SLR Solo Light 10.0 M
10" SLR Solo 3-gun 7.4 M

Spikes Tactical
12" SAR Rail  10.3 U (includes mounting hardware)

Non-free float Handguard Options
DPMS Round Handguard Cap 0.289 U

***Lower Parts***

LPK/ Misc
WOA LPK            5.14 U (Complete but no grip)
NFA Poly LPK     2.0 U
ALG ACT FCG     2.58 U
Geissele SSAE   2.3 U
LPK - FCG - grip   2.58 U
NFA poly trigger 0.26 U
NFA poly hammer 0.20 U
Milspec trigger  1.22 U
Milspec trigger/hammer pins 0.15 U

Steel Milspec Takedown Pins  0.487 C
V7 Titanium Takedown pins  0.268  C
V7 Ultralite Takedown pins  0.176 M

V7 Ultra-light Mag Catch 0.166 M
Steel Milspec Mag Catch
Norgon ambi Mag release 0.50 U
Magpul BAD lever 0.28 U

Safety
V7 Systems 57 degree  0.293 M
V7 Systems Ambi          0.370 M
Steel Milspec                  0.56 U
Badass Ambi              0.67 U
DPMS Ambi              0.80 U

Castle Nut, Milspec  0.60 U
Castle Nut, V7 systems  0.236 M

Endplate, Milspec  0.64   U
Endplate, V7 systems  0.194  M
Magpul ASAP

Stock Hardware/ Receiver Extension
Damage Ind. 7075 Carbine Receiver Ext  3.84 U
BCM 7075 Carbine Receiver Ext 3.88 U
V7 Systems Carbine Receiver Ext  3.6 U

Buffers and Springs
Damage Ind. Carbine Buffer  2.96 U
PSA Buffer                           2.96 U
H Buffer                         3.8 U
H2 Buffer                         4.66 U
H3 Buffer                         5.4 U
VLTOR A5 buffer 5.30 U
VLTOR A5 buffer spring 2.12 U
Rifle Buffer                      5.2 U
Damage Carbine Buffer Spring     1.84 U
PSA Carbine Buffer Springs 1.90 U


Lower Receivers
Northtech Defense Billet   9.25 M
Aero Precision Forged Stripped  8.68 U
Spikes Tactical Forged Stripped 8.4 U
Mag Tactical Stripped       5.88 M
2A Armament Balios Lite Stripped 6.5 M
Kaiser US X-7 Fusion Lower: 5.5 M

Buttstocks

B5 Systems SOPMOD Bravo 8.25 M
B5 Systems SOPMOD Gen2 12.06 U
C.A.R Fiberlight 4.60 M
LWRCI Ultra Compact Stock 7.32 U
LWRCI Compact Stock 8.0 U
Magpul CTR 8.82 U
Magpul MOE   8.0 M
Magpul MOE (no buttpad) 6.98 U
Magpul ACS 14.1 M
Magpul ACS-L 12.5 M
Magpul STR 12.3 M
Magpul UBR 23.4 M
M4 Milspec 6.60 U
M4 Milspec- no sling 5.78 U
MFT Battlelink Minimalist 6.00  M
Rogers Super Spartan 5.2 M
Rogers Super Deluxe 7.3 M
Strike Ind. Viper  6.6 M
Vltor IMOD 9.55 U
Vltor Modstock 8.0 U
ACE Ultralite 8.5 U (includes buffer tube, butt plate, foam pad, castle nut, endplate)
LWRC Ultra-Compact 16.4 U (uncludes buffer tube, spring, buffer, castle nut, endplate, and stock)

Pistol Grips (weight does not include grip screw/ and washer)
BCM Gunfigter Grip
Ergo w/ plug  2.95 U
Hogue 15 degree 1.51 U
Larue A-PEG 4.2 U
Magpul MIAD 3.5 U
Magpulg MIAD (no plug) 3.04 U
Magpul MOE 2.82 U
Magpul K gen1    2.0 U
Magpul K gen 2   2.2 U
Magpul K2 2.60 U
MFT Engage 2.32 M
MFT Engage v2  2.4 M
Milspec A2  2.82 U
Tango Down 3.6 U
Tango Down BG-17 3.32 U
Umbrella Corp 2.58 U


BUIS / Iron Sights
Daniel Defense A1.5 Rear Sight  1.75 U
Daniel Defense Front Sight 1.12 U
KAC 300m Rear Sight 1.48 U
KAC 600m Rear Sight 1.76 U
Magpul BUIS Front 1.2 U
Magpul BUIS Rear 1.3 U
Magpul Pro Front
Magpul Pro Rear
Spikes Lo-Pro billet Front
Spikes Lo-Pro billet Rear
Bobro lowrider (Alu) Front 0.85 U
Bobro lowrider (Alu) Rear 0.85 U
Spikes Micro sights (Alu) Front  = 0.9 U
Spikes Micro sights (Alu) Rear = 1.0 U


Optics
Aimpoint T1 Micro
Vortex SPARC
Aimpoint PRO in ADM mount  10.80 U
Aimpoint T1 w/ LaRue 660  5.78 U
LaRue SPR 1.5  7.06 U
Mueller Speed Shot 1-4x  18.76 U
Primary Arms MD-09 w/ PA riser 6.42 U


Slings
WOTG "Proctor" Sling 1.90 U

Tacticalyellowvisor.com had a list going in a spreadsheet. Not necessarily lightweight but it would be great if we had a master to refer to.

I have some data to add, we probably need weight in grams. Ounces aren't always decimal'd out two positions by scales.

What is the difference between user data and calculated?

Yes, I know about that list. It's getting kind of old and also doesn't focus on lightweight parts. It also doesn't breakdown or even list lower parts kits. So far my purposes, the new thread/spreadsheet was different enough to make it worthwhile.



User Data is weighed by and end-user. Calculated data is calculated or "engineered" without being able to weight it.
I think User Data is the most useful, then Manufacturer, and lastly calculated is mostly an educated guess. Hopefully I can get rid of those eventually.

Your spreadsheet is cool...

Great work so far

tag for updates.

Colt/Rogers super stoc is 6.6 ounces. I think it looks great so people that think they are ugly should keep selling them. :)

http://www.rogersshootingschool.com/products/superstoc.php

They list it as 7.3 oz, which still puts it firmly in "lightweight" territory. I shall add this one to the list. Do you have a pic of one on a scale at 6.6 oz?

No, I got it from this test:
http://blogs.militarytimes.com/gearscout/2012/02/01/buttstock-bashfest-gearscout-finds-out-just-how-far-tough-talk-goes/

They measured in grams, but it's an easy conversion. I have one, but no scale in that range unfortunately.

Excellent thread.

Yes, me too. The problem is their proprietary barrel nut weighs over 3 oz, vs ~1.5 oz for the barrel nut that Midwest Ind. uses or 1.3 oz for the milspec nut.

I'm hoping that people can suggest new products to add to the list and/or provide weights to help out with this project, if they feel it is worthwhile.

Tagged for future updates, sticky this great info

Here are a few more I just weighed:

MOE K2 - 2.6 oz. (w/o screw)
Rainier Raptor - 1.4 oz.
Young Man. Super Lite Carrier (SLC) - 7.1 oz.

Maybe you can put up optics weight like red dots to scopes like Aimpoint Micro with Larue LT660 mount is 6.1 oz.

 




 

I have some more work to do this evening. In the meanwhile, check this out.

Rogers Spartan Super Stock.  5.2 Oz!!

http://www.holsterops.com/spartan-super-stoc

Added some stuff to the OP.  I need a few different measurements if you have these parts, I could use some help.

A2 flash hider
Milspec Charging handle
BCM Gunfighter Small / Large charging handles

Updated the list a little more. Will post up v1.02 spreadsheet this weekend with more stuff.



That is the plan, thanks for the comments.



Added those, thanks for the help.

Palmetto State Armory Milspec Charging Handle - 32 grams
Milspec Firing Pin - 8 grams

Some bad news for V7... V7 Carbine Buffer tube comes in at 100 grams on my scale.

For comparison, the buffer tube that came with my car stock was 105 grams.

Here are some more weights.

BCM BFH 16" Lightweight Barrel (Stripped): 23.80oz or 674.7187g
BCM Upper Receiver (Stripped): 7.00oz or 198.447g

BCM 13" Rail (Stripped): 5.25oz or 148.835g
BCM KMR Alignment Tab: 0.110oz or 3.12g
BCM KMR Barrel Nut: 1.592oz or 45.16g
BCM KMR Attachment Hardware: 0.573 or 16.26g

BCM Midlength Gas Tube: 21.44g
V7 Weapon Systems Midlenth Gas Tube: 26.63g
-----------------------------------------------------------------------
BCM KMR 13 Total Weight: 7.526oz or 213.33016g

BCM Forward Assist: 0.711oz or 20.18g
BCM Forward Assist Spring: 0.058oz or 1.65g
Northtech Titanium Forward Assist: 0.502oz or 14.24g
Northtech Titanium Forward Assist Spring: 0.050oz or 1.42g

BCM .625" Gas Block: 1.926oz or 54.62g


BCM Dust Cover: 0.506oz or 14.35g
V7 Weapon Systems Dust Cover: 0.291oz or 8.26g
Dust Cover Spring: 0.021oz or 0.61g
BCM Dust Cover Pin: 0.211oz or 6.00g

Raptor Ambidextrous Charging Handle: 1.420oz or 40.26g

Misc.
Noveske NSR Keymod Rail Covers:
1 Segment: 0.075oz or 2.13g
1 Lock Segment: 0.077oz or 2.19g
7 Segment: 0.557oz or 15.8g
BCM Keymod Picatinny Rail (5 Segments): 0.445oz or 12.62g

V7 Weapon Systems Midlength Inconel Gas Tube (Without the pin): 0.938oz or 26.62g
V7 Weapon Systems Aluminum Dust Cover: 0.291oz or 8.26g

Blue Force Gear Padded QD Sling: 5.8oz or 164.427g
Magpul 30 Round Pmag, Gen 3: 5.10oz or 144.583g
JP Enterprises Silent Buffer: 7.15oz or 202.6991g

Surefire M600U (With Batteries, No Mount or Tail Cap): 3.5oz or 99.2233g
Surefire Tail Cap (Tape Switch Cap): 0.35oz or 9.922333g
Surefire SR-07 Switch: 1.05oz or 29.767g

A2 flash hider.  61 grams or 2.15 oz
Crush washer.    3 grams or 0.10 oz
DD 12" Omega X with all hardware and nut  15.65 oz
DD 12" Lite rail with large holes top and bottom with all hardware and nut.  14.35 oz
Troy Alpha 11" with all hardware, nut and one QD socket installed.  10.60 oz
Vltor IMOD  9.55 oz
MOE milspec  8.75 oz
My B5 bravo. 9.40 oz? Don't ask me why but it's not even close to what they claim.
FN bolt. 1.50 oz
30 rd USGI mag 4.00 oz
20 rd USGI mag 3.00 oz
30 rd Pmag. 4.75 oz
Pmag cover. .30 oz
Ergo grip with plug, no screw. 2.95 oz
Spike's mid small hand guards  7.90 oz
MOE mid HG. 8.85 oz
MBUS front. 1.20 oz or 34 grams


I can add MBUS front and rear and DD front and rear later.

Thanks for the help!
That DD 12" rail is so heavy compared to everything else I'm not 100% sure if I want it on the list. But maybe I should, so that people have some comparison points...

Thanks for the info.

I was going to build a lightweight AR here are some parts I found;

AP Custom carbon-fiber handguards (claim to be the lightest on the market)
Carbine Length: 7", 3.8 no barrel nut
Mid-Length: 9", 4.5 no barrel nut
Rifle Length: 12.375", 5.4 no barrel nut
XL Length: 15", 6.2 no barrel nut

CAV-15 Lower Receiver now made by GWACS
stripped lower with built-in stock/grip 21.2 M

Blackthorne Polymer Upper Receiver
Says half the weight of aluminum maybe 3.6?

BTW I'm new here so hi

I will be hunting down my scale and adding to this thread ASAP

Parts to add:

Daniel defense 14.5 lw carbine barrel .625 gas block: 20.4 oz
Troy folding rear sight: 1.695 oz
Troy hk folding front sight: 1.46 oz
Matech rear sight: 3.375 oz

I'll try and weight some more parts laying around this week and update what I have

Also, I'm  interested in the weight of LWRC skirmish sight if someone has a set

me too when I get back to the house and have a minute.    I'll contribute a picture of the ACE UL butt being weighed.  That plus a round receiver extention is still the lightest stock system out there i believe.  Unfortunately, it is mounted on a different type receiver extentino than most carbines which makes comparisons difficult.  


Also OP, SLR has a new Solo Lite 3 gun HG out there.  allegidly 8oz for a 15" tube!  That is probably w/ the optional 7075 .9 oz barrel nut though...

http://slrrifleworks.com/index.php?route=product/product&path=66_71&product_id=79

They also list a similar model w/ continuious top rail, a 13" at 8oz and a 15" at 9oz

I'll come back to this later.  Thx OP

ETA: I posted up in SLRs industry section asking for more info about that handguard.  Hadn't got any replies yet.

Okay, new spreadsheet uploaded. A bunch more stuff added to the first posts. This is turning out to be a lot of work, lol.

There are a handful of things I need weights for - for the sake of completeness.
BCM Grip
Magpul MIAD grip
Milspec Steel Takedown Pins (pins only)
LWRC Ultra Compact Stock
And some other odds and ends I can't think of.

Also, the "Test Rifle" on the last tab is now down to 4 lbs, 4oz without cutting or chopping any parts. :)

Milspec Take Down Pins are 14 grams.

FYI, Poly Take Down pins from Accu-Group are 2 grams.

I am interested in an individual components weight, specifically the receiver extension, foam cover and rear shoulder plate. Also the length of it it, from end to end.

If it is less than my car, V7 extension weight, I would consider it. Spikes has a similar butt plate that connects to the QD sling mount on the end of their pistol receiver extension. Very similar to what you have shown.

I just got an MOE K Grip in. My Soehnle scale puts it at 64 grams or 2.25oz.

I know the spreadsheet shows 1.94oz. Probably my scale. That's a big difference though, I can't find the calibrated weight I once had to check it.

Edit: Best verification I have is a Simple Threaded Device. Owner says it weighs in at 2.24oz, my scale shows exactly that. Same scale puts the MOE K at 2.257oz

Link to that end plate thing you speak of?

Yep, I had this on a LW build I did a long time ago, after the famouus "fly weight AR thread" way back."  A 11.5 pencil barrel w/ A2 HG and Hessie receivers  It was nice but I replaced the receivers for fear of an eventual failure.

The short foam sleve (5 3/8th" long): 18g/.635 oz.  I have a 7 3/4" one and am not talking it off, but per my calculations, the long one wold weigh 25.95 g, or .915 oz.  I suppose teh short sleeve would be sufficient even on a longer tube.  

Per an archived thread here, a standard rifle receiver extention is 3.5oz, a "entry" one of 7" is 3 oz.  

As ground down ca 3/16" and w/o either rubber butt pad, the stock is 9 1/2" from the back of the receiver, same as the 3rd position on a 6 position car stock.

Slightly shortened rifle receiver extension, long foam tube, endplate clamp thing w/ sling loop: 151g/5.32oz


Aluminum Butt plate: 83g / 2.93 oz


Complete UL rifle tube assembly (slightly shortened): 234g / 8.254oz  That would be right about 8oz if someone used teh sorter foam tube or just over 7oz if one went w/o sleeve.  Or, that would be just under 7oz of one used a 7" length round "entry" type tube.

1/2" rubber butt pad: 44g/1.55oz

1" rubber butt pad, screws and a little duck tape cause it was too grippy: 87g/3.07oz

For comparison, a steel endplate: .64oz ,steel castle nut: .60 oz  ,  milspec 6 pos rec ext:  3.84 oz(correct?),  milspec M4 stock body w/ loop: 6.6oz, Total: ca 11.68 oz for a mil spec M4 receiver ext/stock assembly.

I like how it is very simple and very strong, not having a receiver extension that has had threads cut into it.  The only problem w/ light stocks such as this is that they  don't make for good counterweights if the barrel s heavy.

BCM MOD1 pistol grip is 3.2 oz on my scale.

Thanks. Dang, she's a pig.



Are you including the screw and/or washer in that weight?

No sir. Just the raw MOE K grip. I am sure there is weight variance from grip to grip, that just seems like more than i would expect unless they changed the molds.

I agree, that is bizarre.  And I was just about to order an MOE K grip to cut down on weight. Maybe not...

Here is the Spike's Tactical Setup that is very similar to this - http://www.ar15.com/forums/t_2_282/246234_Prototype_QD_butt_plate.html

They already sell the Pistol Buffer tube with a QD on the end of it. This plate would just slide on and lock into that QD.

Here are the parts of my current feather weight buffer / stock:



So 244 grams / 8.6oz for the parts to replace the setup you have there. No internals of course in either.

I got an aluminium grip screw in today!

My lower build parts weights so far:



This is a complete functioning lower. I won't have upper weight totals, only estimates, for awhile as I waiting on some work to be completed and some parts to be released.

DD handguards are heavy , relatively speaking .

RIS II -  19.4 M
FSP RIS II -  18.4 M
Mk 18 RIS II -  15.5 M
MFR 9" -  12.1 M
MFR 12" -  14.1 M

is that goint to give you a useful LOP?  I'm going to see if there is another tube that might be as light as the A2 but can secure a normal style endplate.  I like a QD socket and one that is sorty of ambi.  A QD mount in the very end of a stock like taht seems not so ideal.

ETA: the KAK tubes that are 8.45" long are 6.2 or 7.8oz!  What does a milspec 6 position stock weigh again?  Anyone know the weight of regular rifle tube?

Great thread! Some to add that will eventually be going on my lightweight build and other parts I had laying around:

New Frontier Armory Polymer Complete Lower (as it comes out of the box): 1 lb 11.3 oz


M4 stock (from the polymer lower): 7.5 oz


VLTOR stock: 13.9 oz


Brownells Tan Follower 30 rd mag: 4.4 oz


Magpul Window 30 rd mag: 4.9 oz


Brownells 20 rd mag: 2.8 oz


Magpul no-Window 20 rd mag: 3.5 oz


More to follow...

Op, can u add some more carriers to the OP:
Colt half moon (sp1 type)
Spikes milled and drilled steel
Spikes steel lined Ti.

ETA: posted up in ind section about hte drilled spikes carrier....  

ETA: here is  a pic someone posted in my inquiry thread:


That's 10.49 oz.  but that included the bolt assembly, FP, etc.  can we calculate what just the carrier &  key weighs?

Correct me if I'm wrong, but are these the big saver parts more or less in order?
-barrl
-handguard sys
-bolt carrier
-stock butt
- buffer
-muzzle dev
-gas bulk
-end plate
-reciever TD pins
- castle nut

Is that a pretty good priority list?

Would be good to have a spreadsheet that breaks down a colt 6920 with a common rear flip up part by part for reference.

Verification for a Daniel Defense 14.5 inch lightweight profile barrel with .750 gas block.  DD-9083

644.6 grams
22.737 ounces
1.421 lbs

I wouldn't really say so.

1) Barrel
2) Buttstock
3) Handguard / tube
---------------
4) Pistol Grip (can save 1-1.5 oz)
5) Gas block if using 0.625" seat

After that it is somewhat academic. Bolt Carrier Group can save you some weight, but there are functionality concerns with changing the weight there, and they come at a cost premium.  Muzzle device can save you some major weight depending on what you are looking at. Most of the V7 Weapons systems parts are saving you 0.2 - 0.3 Oz, that really is minor compared to other stuff, but noteworthy if you are trying to break under 5 lbs.

Just a heads-up that scale measures in Units not grams, which 1Unit =1.1Grams
Easy way to check is a dollar bill weighs 1Gram your scale will say 1.1

That "g" right past 644.6 stands for grams, some digital paint scales give you the option of grams or units. Dollar bill hit 1.0 exactly just to be sure.

V7 has a lightweight forward assist.

-WEIGHS  9.2 GRAMS            

-APPROX.  55% LIGHTER THAN A STANDARD MIL-SPEC