Improving the 375 H&H

[IvW]

This may well prove to be a interesting experiment. Seems like Gert wants to shoot lighter bullets at higher velocity. I however am looking at shooting heavy bullets at max 2400 FPS, 380 gr Rhino at 2350-2400 fps would be superb. 340 gr softs and solids or 350 gr soft(all Rhino) would be second prize at 2400 fps.....bushveld caliber of note that would be able to take elephant with more authority than the current "legal but marginal" tag.

Should be perfect for Cape Buffalo, coming or going....and old Eland bulls....and...well just about anything....

 

[Gert Odendaal]

This may well prove to be a interesting experiment. Seems like Gert wants to shoot lighter bullets at higher velocity. I however am looking at shooting heavy bullets at max 2400 FPS, 380 gr Rhino at 2350-2400 fps would be superb. 340 gr softs and solids or 350 gr soft(all Rhino) would be second prize at 2400 fps.....bushveld caliber of note that would be able to take elephant with more authority than the current "legal but marginal" tag.

Should be perfect for Cape Buffalo, coming or going....and old Eland bulls....and...well just about anything....

Yes, Ivor and the best of this experiment is you going to do the re-load/load development since you have much more experience than me ...I will hunt thick skin animals like Eland bull and Giraffe as well with the 300 gn bullet and down to 250gn bullet for wart hog and any bushveld game like blue wildebeest and kudu, and maybe if possible 200gn further out on spring buck ..if it is still accurate with these light for caliber bullets it will be a great asset ...

 

[Wyatt Smith]

I’ve considered having mine reamed to 375 WBY. I could always load it back to h&h levels if I wanted. But like IvW I think a 350 at 2400 sounds perfect.

 

[CoElkHunter]

I’ve considered having mine reamed to 375 WBY. I could always load it back to h&h levels if I wanted. But like IvW I think a 350 at 2400 sounds perfect.

From what I understand, you can shoot the H and H in the Weatherby and the cases will fire form to the Weatherby case specs and now you have .375 Weatherby practice brass. So, really no need to load down the Weatherby unless you just want to?

 

[Ridgewalker]

Gert, my experience with 235 grain bullets has been interesting. Typically they don’t have a very good BC compared to 250-300 grain bullets. This causes a more rapid velocity loss even though they start out 200 or so feet per second faster. They are close to even in velocity around the 300 yard mark and then dropping quickly.
Just my thoughts on it. Best of luck in your project!

 

[Wyatt Smith]

That’s my understanding as well. Head stamped brass is about $4 a piece so that’s a downside. The improved speed with the 350s is the main reason would want to re-chamber. I don’t know if I would want to send a 300 grain at more than 2600, but it would do that at a very low pressure.
The H&H feeds like a hungry hog, and gets 2450 with a 300 easy. Then I have to consider the availability of 350 grain bullets that will handle 2400.(Barnes?)
Tough decisions, but the old H&H looks better every time I think about it.

 

[colorado]

Someone on another forum did a test with the 350g Woodleigh soft points at 2150 fps (pretty slow) and they out penetrated the 300g TSX and A-Frame substantially and expanded more as well. I think the 375 H&H shooting these at 2300 fps is a powerful combination. The only reason I rechambered our XCR II to 375 Weatherby was because of poor quality control by Remington. The chamber was rough, the extractor too big to feed Remington factory rounds. So I had my gunsmith put a Sako extractor, rechamber it to 375 Weatherby and weld the bolt handle on. Sad to see Remington go so far downhill The BDL in 270 Win I bought in the late 60s has been flawless, killed many elk, deer and bear, never a failure to function and incredibly accurate to this day.

 

[Gert Odendaal]

Gert, my experience with 235 grain bullets has been interesting. Typically they don’t have a very good BC compared to 250-300 grain bullets. This causes a more rapid velocity loss even though they start out 200 or so feet per second faster. They are close to even in velocity around the 300 yard mark and then dropping quickly.
Just my thoughts on it. Best of luck in your project!

Ridgewalker, great to hear from you again...thank you for this info..it is much appreciated...the twist rate of a .375 H&H Magnum is 1:14 if I am correct?? I was wondering in what velocity band the .375 H&H Magnum Improved Ackley will run..???Will it gives more advantage to a more broad bullet grain weight than the standard .375 H&H Magnum??Since Ivor mentioned he want to do this conversion to up the bullet weight to 380 gn as a dangerous game Buffalo rifle ...? I was thinking more about shooting longer distances...almost all my rifles I currently have are big bore rifles...it would be great if it can be shot into the lower end grain bullets to further out distances ...imagine if a 404 Jeffery can shoot out accurately to 400 meters??? The 375 H&H MAG out to 600 meters..man that will be just great..two in one..a Charge stopper dangerous rifle for buffalo and a sniper rifle out to 600 meters....it is good to have dreams ...

 

[Ridgewalker]

Gert, the standard twist for the 375 H&H seems to be 1:12 from what I researched. All of mine are 1:12 as well.
You must remember when using any of Ackley’s loading to work up to them! They are from a long time ago and powders have changed a lot since then!
I have PO Ackley’s two volume set of books. Here are the pages on the AI version of the 375 H&H:

 

[colorado]

My Rem XCR II in 375 Weatherby (formerly a 375 H&H for a few months) has a 24" 1 in 12 twists. It stabilizes the 300g A-Frames and 350g Woodleighs perfectly. I don't shoot anything lighter.

 

[Gert Odendaal]

Gert, the standard twist for the 375 H&H seems to be 1:12 from what I researched. All of mine are 1:12 as well.
You must remember when using any of Ackley’s loading to work up to them! They are from a long time ago and powders have changed a lot since then!
I have PO Ackley’s two volume set of books. Here are the pages on the AI version of the 375 H&H:

Great, then it would be better not to try and shoot light bullets at all....will follow Ivor`s route to load as heavy as possible for thick skin plains game ...will rather use the 6.5 x 55 Swedish Mauser for the springbuck and blesbuck or the 8x68 S Mauser for the Oryx in the Kalahari next year

 

[Gert Odendaal]

Interesting fact I just received from a rifle barrel manufacturer ..he mentioned witht he 1:12 rifling twist in the .375 H&H Magnum I will be able to use bullets weight 420 gn ...it really would make a great walk and stalk warthog hunting rifle ..for sure....or shooting a tough Blue Wildebeest in thick brush ...or a Eland Bull in thick cover even a Giraffe would be a great stalking hunt...with a 420 gn core bonded bullet from Stewart`s core bonded bullets ..I need to contact Hansie Minnaar to make me a few 420 gn core bonded Stewart bullets for this exercise for sure...I wonder what speed the 420 gn bullet will reach ??? Any opinions members are welcome

 

[Gert Odendaal]

A .375 H&H Magnum Ackley 40 degree caliber shooting a heavier bullet than a 404 Jeffery ...this will be interesting ...would like to have a go at this.

 

[colorado]

My recommendation for what it's worth is load the Woodleigh 350g HD bullets up to between 2300 and 2500 fps. Should kill anything that an expanding bullet is suitable for.

46BHD

HEAVY DUTY

350gr RN SN

50

.356

.323

1900-2500

1.378

coloured black for ID

 

[WAB]

I find the title of this thread interesting. IMO the .375 H&H is one of the most versatile and balanced cartridges we have. I struggle to believe that we can ‘improve’ upon it.

 

[IvW]

I find the title of this thread interesting. IMO the .375 H&H is one of the most versatile and balanced cartridges we have. I struggle to believe that we can ‘improve’ upon it.

Watch this space.....

 

[IvW]

Gert I recon the 380gr Rhino at 2400 fps will be the ultimate. I have some in stock will order some more from Kobus. With x 2.5 expansion and 4 perfect petals it should hammer anything up to Cape Buffalo......

 

[IvW]

We can work on a 300gr longer range load. Something starting out at about 2750 fps should be perfect for LPG at 300 meters+....

 

[HWL]

The .375 Weatherby caliber will not work in SA...head stamps being a challenge , I wonder if the South African police system has the .375 Weatherby on their caliber list as well...

You easily can blow out .375 H&H cases to .375 Weatherby.....as well as to .375 AI.... where is the difference?

Virtually no south african policeman will realize the difference....

I can bring my .375 Weatherby die set in may 2021....

HWL

 

[IvW]

.375 Weatherby here is considered a "different" caliber....cases are difficult to find....
For as AI is the way to go just fire form H&H and the headstamp makes no difference...fire forming to Weatherby you will have to re licence....