Accuload3 lists the case capacity for .375 H&H: 96.7 grains

RCBS.load lists the case capacity for .375 H&H: 92.6 grains

No maker of the brass above specified. This bothered me, so:

Rounded to the nearest grain, only one randomly picked case weighed and filled with water and weighed again:

1) .375/.338WinMag, Winchester brass: 88 grains
2) .375 H&H, Winchester brass: 98 grains
3) .375 Ruger, Hornady brass: 101 grains
4) .375 Weatherby, Norma brass: 111 grains
5) .375/.338 Lapua, Lapua brass: 117 grains
6) .375 RUM, Remington brass: 118 grains
7) .378 Weatherby, Norma brass: 136 grains

Case brass weights for the above:
1) 237 grains
2) 251 grains
3) 263 grains
4) 229 grains
5) 350 grains
6) 277 grains
7) 322 grains

Observations:

A. The .375/.338 WinMag is 10 grains smaller than the .375 H&H, both with WW brass.

B. The .375 Ruger is only 3 grains bigger than a .375 H&H of WW make.

C. The brass in a .375 Lapua is a lot heavier than that of a .375 RUM, though they are only 1 grain apart in water capacity, and the .375 Lapua is also a bit heavier than the larger capacity .378 Wby.

D. The Norma made .375 Wby case is the lightest one for brass content of the whole bunch, though it is over 13% bigger in internal capacity than the .375 H&H.

Possible conclusion:

Brass capacity varies a lot with the maker and lot?

Norma brass is thinner or less dense but of a superior alloy (works well)?

Lapua brass is thicker (for sure, I have sectioned some) and/or denser?

Just in case anyone is interested, here are five fired PMP cases, not trimmed, not de-primed:
All cases are .375 H&H

case weight / with water / capacity in grains of water

1) 279.2 /371.8 /92.6
2) 278.6 /371.2 /92.6
3) 276.6 /369.8 /93.2
4) 280 /372.8 /92.8
5) 279.4 /372 /92.6



From my notes I have these rough capacities. These cases were cleaned, FLR, trimmed, pockets uniformed, then weighed and filled to mouth level with RamShot Big Game:

case weight/ grains of Big Game

ELD (PMC)
1) 252 /90.2
2) 249.8 /90
3) 251 /89.4
4) 252 /90.2
5) 250.6 /n/a

PMP
1) 275.6 /87.4
2) 276 /86.8
3) 274 /87.4
4) 277.2 /86.8
5) 274.4 /87

R-P
1) 254.6 /89.4
2) 250.8 /89.4
3) 251.8 /89.6
4) 254.8 /88.8
5) 254.8 /89.8

W-W
1) 251 /89.2
2) 252.2 /89.4
3) 251.8 /89.2
4) 251 /90
5) 252.4 /89.6

All cases are "regular" brass, not nickel plated.

John,
My brass was fireformed, spent primer left in, no trimming or resizing.

5 of the .375 Ruger/Hornady cases averaged 101.1 grains gross water.

5 of the .375 Weatherby/Norma cases averaged 111.4 grains gross water.

I am surprised at the variability of .375 H&H water capacity from various sources.

Thanks for your .375 H&H samples. They are all within one grain total spread of water or Ramshot for each case.

I marvel at how close your RP and WW brass are to each other.

Seems like RP was always lesser capacity than WW for me, by a greater margin than you got.

I'll have to compare 5 of each of those, later ...

I did the similar test with various brass and this is the results on non fired brass, 10 case average.
WW-88.92
RWS-86.66
RP-85.2 largest variance at 1.2gr
Fed-88.1

Where did you get the Lapua 375 brass??

quote:

Originally posted by RIP:


B. The .375 Ruger is only 3 grains bigger than a .375 H&H of WW make.

So the advantage is?

PMP Brass is typically a little heavier, thicker and less capacity than other brands - very tough, but if you want to load close to max or have a capacity compromised cartridge like a .458, not always the best.

quote:

Originally posted by lb404:
I did the similar test with various brass and this is the results on non fired brass, 10 case average.
WW-88.92
RWS-86.66
RP-85.2 largest variance at 1.2gr
Fed-88.1

Where did you get the Lapua 375 brass??

Leonard,
"Non-fired" brass looks pretty anemic. We like it fireformed, with the shoulders sharpened.

This does point to why my brass capacities are a little larger. I do not resize it before doing the water capacities.

The .375 Lapua brass is obtained by necking up a .338 Lapua Magnum to .375 and fireforming it in my rifle. The same brass might be found in Germany with headstamp that says ".375 Tornado" or "9.5x69mm Tornado."

Measured after fire forming, 5 cases of each, brass weight and water capacity gross in grains:

375 H&H
WW-Super Brass: .... 250.5 ... 97.6
WW-Super Nickel: ... 254.9 ... 96.8
R-P Brass: ......... 258.2 ... 96.8
R-P Nickel: .........261.3 ... 95.3
Federal FC Nickel ... 262.4 ... 95.5

.375 Ruger
Hornady Brass: ..... 264.0 ... 101.1

.375 Weatherby
Norma Brass: ....... 228.3 ... 111.5