How about some help in getting a rundown by this technique:

Use a digital scale for ease, but a conventional balance can also be made to work with greater care.

A. Weigh a fired case with spent primer in place.
B. Leave the case sitting on the scale, then fill it with water (syringe is handy) and get the meniscus at the case mouth within one drop of flat as possible, or just barely convex instead of concave.
C. Subtract A from B to get the water weight.

Here are some of my results:

.375/.338 Win Mag
R-P brass ... 91 grains
W-W Super brass ... 94 grains

.375 H&H
R-P brass ... 94 grains
W-W Super brass ... 97 grains

.375 Weatherby
Wby/Norma brass ... 111 grains

.375 Lapua
Lapua brass ... 118 grains

.375 RUM
R-P brass ... 120 grains

378 Weatherby
Wby/Norma brass ... 137 grains

The .375 RUM is 2 grains bigger than the .375 Lapua, internally.

The .375 RUM case weighs 277 grains empty.
The .375 Lapua case weighs 336 grains empty, being pretty heavily constructed internally, thick headed, shorter and wider than the .375 RUM.

Anybody got some other water capacities, easily done as above, for the record, by brass make and cartridge designation? I started off wondering about Saeed's .375/404 and sumbuddy's .375 Dakota, but this would be a good repository for any cartridge that any kind soul would measure as above, for comparability.

Interesting data, and thanks for sharing it.



To extend the list.



30 Carbine

R-P brass

Empty - 71.2

Full - 92.7

Capacity - 21.5



308 Win

R-P brass

Empty - 174.2

Full - 231.2

Capacity - 57



300 Win Mag

R-P brass

Empty - 238.7

Full - 331.2

Capacity - 92.5



9.3X74R

Norma brass

Empty - 202.5

Full - 287.8

Capacity - 85.3



405 Winchester

Hornady brass

Empty - 204.9

Full - 281.9

Capacity - 77.0



416 Rigby

Federal brass (~ 20 reloads)

Empty - 328.7

Full - 457.9

Capacity - 129.2



Norma brass (2 reloads)

Empty - 338.2

Full - 468.8

Capacity - 130.6



458 Winchester Mag

R-P brass

Empty - 226.3

Full - 319.5

Capacity - 93.2



460 Weatherby Mag

Empty - 344.7

Full - 479.8

Capacity - 135.1



50 Beowulf

Empty - 152.8

Full - 224.8

Capacity - 72.0



505 Gibbs

Empty - 359.1

Full - 532.7

Capacity - 173.6



500 A Square

Empty - 343.1

Full - 484.0

Capacity - 140.9



500 Jeffery

Empty - 327.6

Full - 477.5

Capacity - 149.9



500 AHR

Empty - 338.0

Full - 499.4

Capacity - 161.4



These represent only one (or in some cases 2) case each. I have more data written down in my notes but it is only the net case capacity.



Scott

as will all data received from the internet, you must personally verifiy.

my own meassurements, done at the insistence of ToddE,
500 jeffery
153gr

376 steyr
81 grains

since these two are, for loading purposes, an "on your own" basis, I behooves me to verify.

Scott,
I am intriged at your 10.5 grain difference in 500 AHR and 500 jeffery... I wouldn't have thought the neck would make that much of a difference.

Then again, cases and chambers vary

jeffe

Case capacities: www.geocities.com/CapitolHill/Lobby/1221/case_cap.htm

600Ok is 371grs for the case, 584.5 grs with water for a capacity of 213.5grs with lathe Turned brass. I expect 225 or more with drawn brass.-Rob

Thanks for that, Rob, I will jot it down. Never know when that might come in handy.



And my next contribution:



510 JAB/500 A2 made from 460 Wby brass (it is 2.880" instead of the max 2.900"):

471.6 - 324.3 = 147.3 grains H2O



470 NE, three makes:



BELL (3.248")

467.7 - 322.5 = 145.2



Federal Nickel (3.233")

473.4 - 323.1 = 150.3



Norma (3.225")

470.6 - 320.1 = 150.5



So I better use a couple grains less powder in the BELL than I would in the Federal or Norma brass (the latter two being about identical) to get the same speed with the same bullet.



Another thought is that the 470 Mbogo loaded down to 470 NE velocities, ought to be lower pressure than the 470 NE standard loads. Better go measure the 470 Mbogo case, y'all, and see if it has a tad greater volume than the 470 NE.

470 Mbogo by Quality Cartridge (2.934")
478.9 - 328.1 = 150.8 grains of water.

That settles it, the 470 Mbogo squeaks in at lower pressure than the 470 NE.

With the right powders I use for straight cases
the NE in comparison will give lower
pressure at same velocity and bullet wt.Ed.

Uh, Ed, I forgot the tongue-in-cheek graemlins above, so am including them here.

BTW, the 470 NE is a bottlenecked cartridge, not straight.

The point was that the 470 Mbogo and 470 NE have about the same case capacity.

How high do you think the velocity of the 470 NE with a 500 grainer could be pushed in the Ruger No.1? It could approach 2700 fps if loaded like the 470 Mbogo max loads, eh?

RIP-If cases are good in the base,and a rifle
set up for those pressures, yes it will do that.My
long cased 458HE with about same capacity does over a
100 fps more than that with 500 gr.Ed.

Some more capacities lifted from my notes.

10.75X68 Mauser
(RWS I believe)
93.6 grains

404 Jeffery
(Norma)
116.4 grains

425 Westley Richards
(made from Norma 404 Jeffery)
101.8 grains

450/400 3" NE
120.7 grains

11.2 X 72 Schuler
(RWS I believe not for sure though)
113.1 grains

475 No2 Jeffery NE
(Kynoch old stuff gentlemen)
169.2 grains

505 Gibbs
(again Kynoch if memory serves me right)
177.5 grains (a few grains more than the case I just measured!)

416 Rigby
Federal case fired only once (just returned to me by old friend)
128.2 grains (fired not sized) This is from the same 20 round box as the 416 Rigby Federal case in my previous post, so there has been a significant effect on case volume with 20+ reloads.

Scott

What was the case length on the 416 Rigby when you measured case capacity?

checking out Quickload's capacity estimator using case weight and dimensions and found the following for the 505 Gibbs:
Code:

---

  
            case wt.   H20      Quickload Estimate from Wt.
Horneber     365.5     175.3     183.7
Bertram      334.2     179.6     186.6
 

---

Some published numbers list 181g. Notice the implication of the Horneber wt. Also, the ratio is 2.5% vs 1.6% for QL estimate, hey geometry works!

rgds,

steve