looking to work up .375 H&H load 3000 fps

Hi there. My goal is to develop a .375 H&H load that will push a 260 grain Nosler Accubond to 3000 fps at the muzzle. Has anyone with a chronograph worked up a similar load? This is my first adventure in pushing a load. Highest book load uses Reloder 15 and 2790 fps.

Thanks
Robert Blum

Punch it out to 375 Weatherby.

I believe you will need a 378 Weatherby. You will be about 500 fps short of your goal with a 375 H&H and a good 100+ fps short with a 375 Weatherby.

You are looking to produce 20% more velocity than the standard so one would need to boost pressures 4% for every 1% increase in velocity per Mule Deer's rule. I doubt the brass can handle that kind of stress and I guess it would be pretty hard on the rifle too. I've shot a 378 Weatherby and I did not find it to be a pleasant experience. And it was a good 100 fps slower than the OP's desired velocity.

Rl17 start out with 74-75 work up carefully

I doubt it's possible without using RED HOT loads. I'm battling to get 3000fps out of my 375 Rem Ultra Mag when using 260gn Accubonds. My rifle has a 25" bbl.

Originally Posted by rblum100

Hi there. My goal is to develop a .375 H&H load that will push a 260 grain Nosler Accubond to 3000 fps at the muzzle. Has anyone with a chronograph worked up a similar load? This is my first adventure in pushing a load. Highest book load uses Reloder 15 and 2790 fps.

Thanks
Robert Blum

You can't get there safely

Drop down to 235's.

Originally Posted by woodmaster81

I believe you will need a 378 Weatherby.

Pretty much.

Maybe 2750 fps with sane pressures.......maybe

Easy Peasy.

You just need a case full of RL-17 and a 30" barrel.
If you don't have a 30" barrel, don't even try:

Code

Cartridge          : .375 H.& H. Mag.
Bullet             : .375, 260, Nosler AccuBond 54413
Useable Case Capaci: 77.767 grain H2O = 5.049 cm³
Cartridge O.A.L. L6: 3.600 inch = 91.44 mm
Barrel Length      : 30.0 inch = 762.0 mm
Powder             : Alliant Reloder-17 *T

Predicted data by increasing and decreasing the given charge,
incremented in steps of 0.625% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step    Fill. Charge   Vel.  Energy   Pmax   Pmuz  Prop.Burnt B_Time
 %       %    Grains   fps   ft.lbs    psi    psi      %        ms

-06.3  100    75.00   2862    4729   51334   6789    100.0    1.373
-05.6  100    75.50   2880    4789   52487   6804    100.0    1.360
-05.0  101    76.00   2898    4849   53670   6818    100.0    1.348  ! Near Maximum !
-04.4  102    76.50   2916    4909   54882   6832    100.0    1.335  ! Near Maximum !
-03.8  102    77.00   2934    4969   56127   6845    100.0    1.322  ! Near Maximum !
-03.1  103    77.50   2952    5030   57402   6858    100.0    1.310  ! Near Maximum !
-02.5  104    78.00   2969    5091   58710   6871    100.0    1.298  ! Near Maximum !
-01.9  104    78.50   2987    5152   60051   6883    100.0    1.286  ! Near Maximum !
-01.3  105    79.00   3005    5213   61430   6895    100.0    1.274  ! Near Maximum !
-00.6  106    79.50   3023    5274   62846   6907    100.0    1.262  !DANGEROUS LOAD-DO NOT USE!
+00.0  106    80.00   3040    5336   64295   6919    100.0    1.250  !DANGEROUS LOAD-DO NOT USE!
+00.6  107    80.50   3058    5397   65788   6930    100.0    1.239  !DANGEROUS LOAD-DO NOT USE!
+01.3  108    81.00   3075    5459   67319   6941    100.0    1.227  !DANGEROUS LOAD-DO NOT USE!
+01.9  108    81.50   3093    5521   68891   6952    100.0    1.216  !DANGEROUS LOAD-DO NOT USE!
+02.5  109    82.00   3110    5584   70501   6963    100.0    1.205  !DANGEROUS LOAD-DO NOT USE!
+03.1  110    82.50   3127    5646   72167   6973    100.0    1.194  !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 3% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 3% relative to nominal value:
+Ba    106    80.00   3076    5463   68353   6807    100.0    1.222  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 3% relative to nominal value:
-Ba    106    80.00   2999    5191   60413   7046    100.0    1.281  ! Near Maximum !

I get there with my 375 RUM. I get 3000 fps with 270 gr. Speer and 97 gr. of Alliant R-23. Factory 26" barrel. I would not even try with a 375 H&H.

TINSTAAFL

I’ve seen printed loads for the 375 Weatherby 260 grain at 2900fps.
I have a 375 H&H AI which has a small amount of case capacity greater than the Weatherby, I would not likely try to get to 3,000 FPS with my 26” barreled rifle.
I can only imagine what pressure you’d need to get to 3,000 FPS and with a 260 grain bullet out of a 375 H&H.
I would not do it and I’d not recommend it!

Like others have posted, I don't think you can safely get 3000 fps with a 260 grain bullet from a standard .375 H&H.

The best that I've got from my 26" barreled .375 RUM is 3043 fps with 270 grain TSX bullets and 2898 fps with 300 grain Partitions.

I have a 24” barreled 375 Bee, I can push a 260gr AB to 3000fps...but the brass is toast after 2 firings.

If you think you can push this velocity from a H&H case...expect a stuck case, case head flow into the bolt face and a mallet to open it, if it opens at all.

Cheers.

Anyone dead yet?

The big question is why?