Home Forums Hunting & Shooting Express Rifles and Big Bores Only 375 Weatherby vs 375 H&H

Tom Smith,
The 375 Wby can add a good deal of velocity especially with heavy bullets but if it's "that much better" is up for grab. Some think so and it certainly works on big stuff with proper bullets, particularly monolithics.

Personally, I am more than satisfied with the 375 Holland and Holland, but that has to be a personal choice and since I have never had any problems killing anything with a 375 H&H it is my choice..If I want more then I drag out my .416 Rem.

Another plug for the .375 Roy.

H-414 is one of my favorite powders. You can get some really good numbers out of it. Especially with a 26" barrel. Mine's right at 8 1/2 lbs. scoped and loaded. It's on the snappy side when it goes off. But not terribly hateful.

Previous poster was right. If they'd put it in a Mark V synthetic, they'd sell like hotcakes.

I have been a life long keen 375 bore person and that interest has extended to observing other people with their purchases.

Over the years in Australia I have seen many people who buy a 375 and especially the CZ and with the intention of rechambering to 375 Wby. Similar situation exists with the Wby Mark V Synthetic in 375 H&H. However, when they get their 375 H&H and test a few loads and sight in etc. the desire for more power and recoil is at an all time low Used to see the same thing with CZ 458 Winchesters that were purhcased with rechambering to 458 Lott being the intent.

If you read these forums enough then after a while the 375 H&H and 458 Winchester take on the dimension of a low powered calibre suitable for indoor use.

I think that The 375 AI is the only way to go if you want to excede H&H velosities. Why start out with a big powder volume of the 375 Roy and its frebore? The 375 AI round will do anything that the Roy will do: and have more barrel life. It's no harder to fireform, runs standard 375H&H loads if necessary, and must hold at least as much powder.

For loading data use published 375 Roy data to start. I stay away from all of the Weatherby rounds on purpose.

I don't think barrel life is much of a factor in a round that pounds.

I on the other hand , can see little reason to choose the AI version over Weatherby . Barrel life ahould be as near identical as you can make it , at any rate these are not cartridges for shooting gophers or groundhogs (well , maybe Dober would..grin) The powder capacities are about the same and the freebore is a moot point .


The Roy version has several advantages going for it in my book , including the factory brass if you so desire , readily available loading data , and at least 2 brands of factory ammo . Also maybe eaiser feeding . The Roy feeds just as well as the vaunted H&H case IME . Rounded corners slide easier than sharp corners .


Some of the Weatherby cartridges are classics in their own right , the 300 and 375 being 2 .

"a round that pounds", I likey that...

Dober

Laffin here... .

IME the 375 AI pushes a 275 gr BBC at a bit over 2900 fps;about the same as a standard H&H pushes a 250;the H&H round will do an easy 2750 fps(maybe a hair more depending on the barrel used) with the same 275 gr bullet and RL15.I suspect the velocity differences will hold true with all bullet weights commonly used.

The AI can use slower powders than the standard H&H,and more of it for that 100-150 fps gain, which translates into a substantial jump in recoil for the AI. Only the shooter can determine if it's worth the recoil increase.For me it never was...

There isn't enough difference between the AI and the Weatherby to spit on....

Another red-herring I have to snicker at is the issue of "Weatherby Freebore." For one thing, all of my older Weatherbys that have a lot of it, are very accurate (sub MOA) and freeboring was the thing to do with the available powders at the time. With the advent of slower powders we have today, I think most Weatherby haters will be surprised at the amount of freebore in modern Weatherby rifles.

The 375 Weatherby was a stepping stone for them eventually leading to the 378 that with modern bullets is an absolute hammer and while not as popular as the H&H of which I own two, ammo is readily available worldwide. Try finding ammo for your "AI" in Africa or for that matter ANYWHERE in the US if the airlines gooned up your luggage. Lastly, I must admit I was never impressed with Ackley. If his stuff was so good, how come we don't see them like we do Weatherbys?

i haven't played with RL 17 in my 375 roy yet , but I suspect it will push a 270 grainer very, very close to an honest 3000 fps.......H4350 or RL 19 will easily get 2950 .

when the same barrel had an H&H chamber , I could barely get the 250 Sierra to +2800 . A 235 barnes would do a little over 2900 , this with RL 15 .

sd: I just clocked the 250 from my 375H&H at 2940 recently,a velocity level I have been getting with no ill effects since the 80's;barrel is a 24" Krieger,but have gotten similar results from the pre 64 M70 barrels I have shot extensively,many of which are somewhat oversized.

So much of this depends on the barrel,throating, etc.

Bob , I think it has something to do with the long factory throating my M-70 came with , at any rate it seemed there was a brick wall you would hit where adding more powder would not increase the velocity .

Another 375 in my possesion , a Whitworth , would just barely make 2700 with 270 gr without sticky extraction , no matter the powder tried . It was a stretch to get 250 s to 2750 with RL 15 .

I've read alot on the net about hot 375 H&H loads that would do well over 2800 with 270 s , but I couldn't get there with the 2 I tried....admittedly a small sample .

I agree with Mike378..One thing I have noticed over the years is that the 375 Wby, the 458 Win. and the 44 magnum and those calibers above them are never in much used condition and they all have prestine bores! Go figure!

SD: Yup it's all in the alchemy of groove diameter, bore smoothness, throats, etc.,mysterious factors beyond my ability to comprehend....also certain bullets measure different,have more or less bearing surface,etc.I measured some 270 cal 130 gr screw machine partitions this morning that all measured .276...add that to a barrel slightly oversized,and who knows what will happen!

And we wonder why we all wind up with different results!

One guy doesn't understand using a Wby that another posters swears by, when a IMP ackley is just almost as good and I don't see either that much better than my beloved .375 H&H since it has never failed me on anything, anywhere.

Darn it, I have believed that a 250 gr. Sierra at 2800 FPS in my H&H would work on about anything under all circumstances?? Now I'm being told 2950 to 3000 is better, I suppose it is but for what is my next question?

Darn, guess its still up for grabs which one you pick!

I have both calibers but that Wby .375 will leave a lasting impression on your upper torso once you get over the 2600fps mark. I myself see very little difference between the two as Mr. Atkinson stated.

"Improved"375H&H is an oxymoron.....

I have no reason to disparage any of the other .375s, but I just took a 9'-2" brown bear in SW Alaska with a 27-7/16" skull. I shot him offhand at 97 yards with the .375 Wby. My guide who had been involved in more than 30 brown bear kills as a hunter and guide over 23 years, said that it was the quickest non-head-shot kill he had ever seen on a brown bear of any size. The bear bolted forward (what we later measured as) about 25 feet, spun violently to his right (guide said to bite what was biting him) and drove his face in the ground. The bear's movements only lasted about 1.5 seconds after the shot. No blood trail to follow.

300gr NP exited the muzzle at about 2,830 fps and entered behind the right shoulder at a little more than 2,600 fps, blew up both lungs and who knows what else, and exited effortlessly into the blueberry bushes on the other side.









My guide, with all of his experience, was amazed. I'm sure other .375s would have done well, but I'm not selling my .375 Wby anytime soon.

More details here.

Congrats on the bear!

MH: Congrats! Nice bear!Typical 300 gr Nosler performance.

Yes, 375's work...all of them.