Weight of Brass

[Loonster]

I am trying to figure out the combat load weight of various cartridge sizes.  To do that, I need to find the weight of the rounds.  Calculating this off components should be easy... Bullet weights are a given, powder weights are easy to look up, but brass weights are hard to find.
 
I am most interested in 6.8 SPC, 6.5 x 39, .243 Win, and .260 Rem. I also need 5.56 nato and 7.62 nato as baselines. (Any others that I should add?)

So far I have

5.56 Nato = ~ 94 grains
6.5 x 39 = ~ ?? grains
6.8 SPC = ~ 120 grains
.243 Win = ~ 175 grains
.260 Rem = ~ 175 grains
7.62 Nato = ~ 175 grains
LR Primer = ~ ?? grains

Could you please fill in the blanks and check the others for me? The only one I'm confident about is 5.56 nato. 6.8 and 308 were pulled off various forums during hours of google searches for weights. .243 & .260 are assumed to be same as 308. I'm also interested in large rifle primer weights (unimportant since each rifle has same primer. Added just for curiosity of final weights)

Thank You

[MickeyC]

Different cases are different weights. Particularly noticeable is the difference between military and civilian brass.

[Loonster]

True, but it's a negligible amount for the purpose of my study.  I'm hoping I can get each rd guess within 7 grains of an actual rd. Maybe more information about what I'm doing would be useful.

I often see people use weight as a reason on why one cartridge might be better than another. Very rarely does someone post any data about it (and when they do, it's very vague). Since I am unable to google a good source, I decided to make my own.

I decided to format the data in three ways:
- Weight per magazine (1, 2, 4, 6, 8, 10)
- Weight per rd count (50, 100, 150, 200, 250, 500, 1000)
- Rds per lbs (1, 2, 4, 6, 8, 10)

I decided to use the following cartridges in 2 common bullet weights each:
- 5.56 Nato (62, 77)
- 6.8 SPC (110, 115)
- 6.5 x 39 (108, 120)
- 7.62 x 39 (123) (only 1 common)
- .260 Rem (120, 130)
- 7.62 Nato (168, 175)

I have written the excel spreadsheet already but I don't want to post the output until the input is more accurate.

I want to find before posting:
6.5 x 39 brass weight
7.62 x 39 brass weight 
Magazine weight: 5.56 nato (30 rd), 7.62x39 (30 rd), 7.62 Nato (20 rd)
LR Primer Weight

The only mag that I can find the weight of is the Pmag 30rd. (0.3 lb.) Everything else I find is listed as relative to something else. (1.4 ounces heavier than standard, 40% lighter than standard, etc). I would like to use polymer mag weights in spreadsheet, but I am willing to do it in other materials.  I don't expect 7.62 x 39 ever to come out in polymer, so that one can be whatever.