I found a deal on H380 and being one who likes a bargain when it presents itself I bought some. Now various load data reads that H380 should work in the 375 H&H with 270 grain bullets.
Anyone used H380? or should I find another use for it?

I haven't used H-380 in a .375, but it is very close in burning rate to its stablemate, H-414, which I have used in the .375. There's no reason it shouldn't work fine, but while its burning "rate" is similar to H-414, it has slightly different burning "characteristics". Powders can vary in how they act with case size, bore size, and bullet weight. So, I would not suggest interpolating data from a similar powder, but rather starting with data from a known source and working from there.

Follow Hodgdon's load data and see what happens.

little bit fast i think plus you will end up with alot of vacant space in the case

My limited experience with the 375 is that it is one of those cartridges that is very forgiving in what components you use. Seems like almost any powder within reason will yield good accuracy and velocity. Or maybe it's just my rifle...

The only way you will really know how H380 works in your rifle is to try it. I just tried Win. 748 in my M70 .375 H&H with the 300 gr. Barnes TSX and got excellent accuracy. Some of the 3-shot groups were under .5" and most under 1". Win. 748 is a little faster than H380. The Barnes manual lists Win. 748 as the most accurate load for the 300 gr. TSX. The powder is slightly compresses in both Win. and Privi brass. Based on my results, I think H380 is definitely worth trying in your rifle.

Run through QuickLoad and it should be fine.

What 270gr bullet with what COAL exactly?

Jiri

3.605, I was fortunate enough to pick up a bunch of Hornady 270 round nose bullets for general use

Cartridge          : .375 H.& H. Mag.
Bullet             : .375, 270, Hornady RN 3715
Useable Case Capaci: 85.430 grain H2O = 5.547 cm3
Cartridge O.A.L. L6: 3.605 inch = 91.57 mm
Barrel Length      : 24.0 inch = 609.6 mm
Powder             : Hodgdon H380

Predicted data by increasing and decreasing the given charge,
incremented in steps of 1,213% 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

-12,1   82    65,91   2362    3345   37779   8038     95,5    1,442
-10,9   83    66,82   2393    3433   39208   8153     95,9    1,416
-09,7   84    67,73   2424    3523   40690   8264     96,4    1,391
-08,5   85    68,64   2455    3614   42226   8372     96,8    1,367
-07,3   86    69,54   2486    3705   43819   8477     97,2    1,344
-06,1   88    70,45   2517    3797   45472   8577     97,6    1,320
-04,9   89    71,36   2547    3891   47187   8674     98,0    1,298
-03,6   90    72,27   2578    3985   48965   8767     98,3    1,276
-02,4   91    73,18   2609    4080   50812   8856     98,6    1,254
-01,2   92    74,09   2639    4176   52728   8941     98,9    1,233
+00,0   93    75,00   2670    4273   54717   9021     99,1    1,213  ! Near Maximum !
+01,2   94    75,91   2700    4371   56783   9097     99,3    1,192  ! Near Maximum !
+02,4   95    76,82   2730    4469   58929   9168     99,5    1,173  ! Near Maximum !
+03,6   97    77,73   2760    4568   61159   9235     99,7    1,153  ! Near Maximum !
+04,9   98    78,64   2790    4668   63477   9297     99,8    1,135  !DANGEROUS LOAD-DO NOT USE!
+06,1   99    79,55   2820    4769   65887   9353     99,9    1,116  !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 5% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 5% relative to nominal value:
+Ba     93    75,00   2730    4468   59786   8920     99,9    1,167  ! Near Maximum !
Data for burning rate decreased by 5% relative to nominal value:
-Ba     93    75,00   2599    4048   49710   9011     97,2    1,265

Post edited for better readability.

Jiri

quote:

Originally posted by Gojoe:
I found a deal on H380 and being one who likes a bargain when it presents itself I bought some. Now various load data reads that H380 should work in the 375 H&H with 270 grain bullets.
Anyone used H380? or should I find another use for it?

Not trying to sound snotty, however H380 data is easily available right on the Hodgdon website.
http://www.hodgdonreloading.com/data/rifle

Cheers,
Mike

GoJoe Looking in my reloading record book I see that I tried some H380 with the 270 Hornady in an old 375 I have. The record shows H380 grouped well but the point of impact in MY rifle was about 6 inches lower than other loads I had tried. For that reason I did not use it any more in the 375. Results in your rifle may be quite different

quote:

Originally posted by Redstone:

quote:

Originally posted by Gojoe:
I found a deal on H380 and being one who likes a bargain when it presents itself I bought some. Now various load data reads that H380 should work in the 375 H&H with 270 grain bullets.
Anyone used H380? or should I find another use for it?

Not trying to sound snotty, however H380 data is easily available right on the Hodgdon website.
http://www.hodgdonreloading.com/data/rifle

Cheers,
Mike

Oh, I have data, the Speer #11 and Lyman #46 and other manuals, plus the web. I just wonder how it worked out in application.
Snowman was able to provide some of what I'm looking for.
Cheers

quote:

Originally posted by Gojoe:
I found a deal on H380 and being one who likes a bargain when it presents itself I bought some. Now various load data reads that H380 should work in the 375 H&H with 270 grain bullets.
Anyone used H380? or should I find another use for it?

I'm going to guess the deal you found was at bullets.com

Same deal I found, 16# worth, Can't beat half priced powder

Just checked, and yes all the power is gone.

Slightly off topic but I've had wonderful results with 4064 and 300 grain bullets in the 375. Based on 4 rifles, 4064 shoots phenomenally well in all and for some reason I don't understand (burning rate and/or pressure curve shape?) the "felt" recoil is different with a less punishing roll to them. I've decided it's the only powder for me in the 375 and a couple of other fellows who have have tried the combination came up with similar results...

4064 is my current go to powder for almost everything. I've had wonderful results with 260 Nosler AB and Hornady 270 RN. Locally reloading powder components are very limited. Being flexible with different components is a must.