.375 A.I. opinions....

25 February 2002, 20:51

Greetings,

I would be interested in hearing from those of you who have "improved" your .375 H&H arms.

This is something I am considering and I am curious if it really makes a difference regading case life.

I have also been told that throat erosion is reduced when using the improved cartridge.

All comments appreciated.

Regards,

~Holmes

26 February 2002, 07:14

<Don Martin29>

I have a .375 Improved with a 22" Douglas bbl. I don't really understand the concern about bbl life. I may have only fired this gun 300 times in 15 years. One trip to the range to check the sights and then you know you have been to the range.

Case life is good in both the improved and regular .375 H&H.

If I had it to do over I would have just bought a M-70 in the regular .375 H&H. What happened was that while this gun was being made for me a pre-64 came along at a low price. The old M-70 is far superior to the Sako action on the custom rifle. If I did not like the gunsmith who made up the rifle for me I would get rid of it.

I don't see much difference in performance.

26 February 2002, 07:54

Atkinson

I'm with Don, the only difference that I could see was more recoil and muzzle blast..

An "Improved 375" is an oxymoron...can't be improved and if it's not powerfull enough then get a 416...

------------------
Ray Atkinson

ray@atkinsonhunting.com
atkinsonhunting.com

26 February 2002, 08:00

HunterJim

Holmes,

If you improve the cartridge case, and then load and burn *more* powder I don't see just how to reduce throat erosion.

I remember in the late 50s and early 60s when the venturi shoulder was supposed to be the magic way to everything better in wildcat cases, at least Controlled Cumbustion Cartridge Co. said so. It was really wide open back then before the hobbyist chronographs arrived and burst a lot of bubbles.

Dr. Atkinson has the prescription here in recommending a .400".

jim dodd

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"if you are to busy to
hunt, you are too busy."

26 February 2002, 10:51

Holmes

Gentlemen,

Allow me to elaborate upon my query.

My interest is not based upon velocity gains. The H&H ballistics is fully satisfactory for my purposes. Most of my favourite loads are below published maximums as that is where my rifle seems most accurate. If I were to opt for the Improved version, I would be loading for accuracy once again, not maximum velocity. I have larger calibre arms if the need for a substantial power increase arrives.

As I use the .375 for the majority of my shooting and hunting, barrel life is a real issue. My M70 easily sees 1500 rounds annually. Many long-range high velocity aficionados have postulated the theory that the improved shoulder reduces powder erosion in the throat of the barrel. As I am not a gunsmith, I do not fully understand how or why this could be. Frankly, I was hoping one of you might be able to explain it to me!

Case life is another issue. I find it necessary to frequently trim my brass and the improved shoulder is said to reduce brass flow. This makes sense to me with neck sized hand loads.

The rifle is going in for a couple of sight modifications and I thought this might be a good time to ream the chamber if the Improved version really had any benefit with regard to throat life and case life.

Regards,

~Holmes

26 February 2002, 11:57

<Don Martin29>

Unless there is something wrong with the chamber then leave it alone. Sticking a "improved" reamer into a .375 H&H is like painting over the Mona Lisa.

I don't think there is anything to shoulder shape and erosion. There is a theory like that where the shoulder angle intersects with the neck or not. It's just a pipe dream to me.

With the large bore volume of the .375 I don't see any problem with erosion. Many military bbl's of .30 cal last over 10,000 rounds and at that count respond well to laping and go on for more.

I thought that PMVF pioneered the venturi shoulder and not CCC. I think Roy W. got his idea there.

26 February 2002, 11:59

Reed

The decrease in body taper and a sharper shoulder might indeed net you the increase in case life and quite possibly an increase in accuracy as well. It will also help reduce case lengthening. I don't think anybody would dispute those "assumptions."

I don't think those changes would gain you anything in terms of barrel life. In fact, they will more than likely cost you barrel life for previously stated reasons (burning more powder, etc.).

At this point I would be interested to know what your use of this particular rifle might be? Should it be non-DGR with potential for longer shots then it may be a desired change. Should it be DGR you may want to stay with the tapered case, etc., to aid in feeding, etc.

My 2 cents worth.

Reed

P.S. You may want to look elsewhere, non "Big Bores" forums/books, for some discussions on why the minimum taper, sharp shoulder is desirable for accuracy. There's no small coincidence that the PPC BR type cartridges are minimum taper with healthy shoulder angles...

26 February 2002, 14:48

HunterJim

Don,

As I recall PMVF were pioneers, but CCC did the horn tooting.

Of course that was a few years ago.

jim dodd

------------------
"if you are to busy to
hunt, you are too busy."

26 February 2002, 16:12

Holmes

quote:
Originally posted by Reed:
The decrease in body taper and a sharper shoulder might indeed net you the increase in case life and quite possibly an increase in accuracy as well. It will also help reduce case lengthening. I don't think anybody would dispute those "assumptions."
Agreed.
I don't think those changes would gain you anything in terms of barrel life. In fact, they will more than likely cost you barrel life for previously stated reasons (burning more powder, etc.).
This is the way it would seem to me also.
At this point I would be interested to know what your use of this particular rifle might be? Should it be non-DGR with potential for longer shots then it may be a desired change. Should it be DGR you may want to stay with the tapered case, etc., to aid in feeding, etc.
I use the rifle in the same manner many people use a 30.06; all purpose firearm. Antelope to moose. Coyotes and jackrabbits when they present themselves.
Thanks for your comments and suggestions, Reed.
~Holmes

26 February 2002, 17:33

John Ricks

Recoil, Recoil, Recoil, substantially more than a standard 375. We were getting 2775 ft/sec with 300 gr A-Frames. A 9 pound rifle is downright unpleasant to shoot off the bench. And, the high velocities obtained, especialy with 270 gr bullets, really makes bullet problems at close range a reality.

One of my older partners in crime, now gone to gunsmith heaven (it's really down, not up!!!) told me the reason Roy used the double radius on his cartridges was the reamers were harder to copy!

26 February 2002, 17:58

John Ricks

Rest of the Story: The owner said Enough, and I pulled the barrel & installed a no. 6 Pac Nor, and chambered for a 416 Remington.

26 February 2002, 18:04

Holmes

quote:
Originally posted by John Ricks:
Recoil, Recoil, Recoil, substantially more than a standard 375. We were getting 2775 ft/sec with 300 gr A-Frames. A 9 pound rifle is downright unpleasant to shoot off the bench. And, the high velocities obtained, especialy with 270 gr bullets, really makes bullet problems at close range a reality.
I am aware of these conditions. As I stated, my primary interest was extending case life and throat life. Increased velocity is not the target as I would simply load for a sweet spot around the original H&H levels.
My rifle weighs in at 10.5#. I brought it to this weight to make a comfortable weekly shooter out of it which it is.
One of my older partners in crime, now gone to gunsmith heaven (it's really down, not up!!!) told me the reason Roy used the double radius on his cartridges was the reamers were harder to copy!

An interesting anecdote. He was a clever one, eh?!

~Holmes

26 February 2002, 19:44

tsturm

If you like the tried and true .375 H & H and it isn't broke, Dont fix it? In my 24"bbl whitworth .375AI I get 2775 fps with 300g spbt. and 100fps less with 300g rn. At 10# and with a sorbathane? recoil pad it isn't to
bad on the shoulder! (I put 20 rounds through it today, 10 fireforming & 10 of the AI cases for groups) Good luck!!

27 February 2002, 05:30

dan belisle

I shoot both the 375 H & H and a 375 Wby. The Wby is my choice for anything that requires a little range. I tried all the loads I could find in the Wolfe wildcat books and the Ackley books, some of these boys dance on air. (eg-91 gr 4350 behind 300 gr Nosler) I tried that load, and got no pressure signs that I could see, but it was going 2925 fps, which has got to be too hot a load. That's in the Wby of course, 27" barrel and freebore. The best load in the regular 375 nets me 2600 fps (24" barrel, standard chamber, Whitworth mauser). Accuracy is a toss up. With the loads they like they are pretty much equal. If I load the Wby down to H & H speeds, it would stand to reason that (because of the bigger case) I would still have to burn more powder to equal those speeds. As for recoil, well the Wby weighs 2 lbs more than the Whitworth, so it's actually a little easier to shoot. I still like the improved version, but I think it's got a speciallised niche. FWIW - Dan

03 March 2002, 22:33

Socrates

If you use a light bullet, like 200 grain, in this caliber, what's your max velocity for HH and WBY?
gs

04 March 2002, 03:13

John Ricks

Holmes, not only was Roy a clever one, he was a marketing genius! We all cuss and discuss the Weatherby rifles and cartridges, but they made Roy a wealthy man and financed many a nice hunting trip for him. What more could a man ask for? Especially when Roy started out in a garage with practically no money to speak of. His success is a true American dream story.

Back to the 375 AI, with your 10-1/2 pound rifle weight, recoil really will not be a problem. I look on this as a long range cartridge, and a properly set up rifle would make a supurb Elk and Plains game gun.

------------------
Currently in Exile on the Beautiful Olympic Peninsula of Washington State.

My Warden sometimes allows me to respond to email. NEW Address is rifles@earthlink.net

***********Jail Flash*******
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[This message has been edited by John Ricks (edited 03-03-2002).]

04 March 2002, 06:42

<Don Martin29>

I really don't think Roy W. ever had a orginal idea. He was the Barnum and Bailey of firearms. Now promotion is a good thing when done with skill and Roy W. was very skilled at that.

But clever in a technical sense. Hardly. The took the idea for the cartridge designs from the PMVF work. Powell and Miller were gunsmiths who had made rifles with (V)venturied (F)freebore chambers. So Roy W. just copied this idea without credit to Powell and Miller. The chamber reamers cost more to make but are not patented. Nor do they produce any benfit.

The freebore throats are old ideas from military developments. A freebored throat has problems and the benfit of higher velocity. No target cartridges are freebored.

But just to build a company like Weatherby did takes lots' of talent and effort and my hats off to him. He has also 100% pro gun as far as I can tell.

He did make popular diamond inlays and a gaudy look. There is a market for that.

Early Weatherby rifles had CRF but the Mark V got away from that. Having owned a .378 Weatherby I can tell you that you don't want one. They are clumsy, no CFR, freebored, velocity is too high for good bullet action and the MV-V action is a poor design. Mine was made by Sauer.

In summary the Weatherby co. has guns made that satisfy a nich market. Good for them.

04 March 2002, 07:50

<Don G>

I think the 40 degree shoulder might improve barrel life because it holds the powder in the case better than the 15 degree(?) of the H&H.

I still wouldn't do it. The shallower angle gives very reliable feeding.

Don

04 March 2002, 08:45

Santala

I have been shooting a 375 AI for some time. It is a 10 1/2 pound rifle and I have never noticed any real problem with recoil. I shoot most 300 gr through the 24 inch barrel at 2750fps+ depending on the bullet make. I have started loading the 265 gr HV GS Custom at around 2950 and the 270 gr FN. At these velocities I have an excellent long range rifle.

I'm interested to see how the new 350 gr Woodleigh bullets preform at 2400 fps+ through the 375 IA.

Steve

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Every man dies, but not every man really lives!!

04 March 2002, 14:32

dan belisle

Socrates, I haven't tried the 200 gr bullet in any of my 375's. The lightest I've used is the Hdy 220 gr. It's not used for hunting really, just for popping coyotes and rabbits to stay in practice over the winter. I get 3000 fps from the H & H and 3200 fps in the WBY. They're sure fun for plinking though. - Dan

06 March 2002, 22:50

Socrates

Dan:
Had a very intresting day. Didn't get my 06 yet, being rebedded.
However, kicked around the shop, found a used press, bought some 375 H&H, and, I was just thinking, it doesn't look THAT big, at least not when you are used to 45 Colt, with 325 grain LBT's on a daily basis.

Still, it does kind of dwarf a 30-06.

And, I think that's the problem. It just is too darn efficent a cartridge, much like the 308, or 06.

It should well, LOOK a lot bigger for what it gets done. The 375 RUM is WAY sexier looking, hell, even the 300 RUM is sexier looking.

I was just reflecting upon your comments. You get a 220 grain bullet, at 3000 fps, and use it on coyotes????

Now, 300 Magnum guys heaviest bullet is about 220, with, maybe, the sierra 240 hpbt as the heaviest. Do they get these going at 3000fps? Don't know.

375 doesn't look like it takes that much powder, but, the ballistics are pretty scary, and, I would not want a four inch exit wound, from a 375 softpoint, anytime soon...

Anyway, how do those 220's work on coyotes?

I've got a guy around here, that fires at coyotes on a ranch. Wonder if he would test my 375 on one???

------------------
I love 45
santilli@singleaction45.com

07 March 2002, 04:49

dan belisle

Why don't you ask him if you can tag along? Most shooters enjoy the company, and are usually happy to help out. I use the 220's on coyotes for practice in the winter. The recoil is light, and accuracy is reasonable (about 1.5 moa). They turn a coyote pretty much inside out. As the pelts aren't worth much right now, and all the farmers I know with livestock are glad to be rid of the varmints, this works out well. Spring time (which hasn't made it here yet, it's -28 degrees today- in town, 10 degrees colder out in the sticks)is when you get a lot of shooting opportunities, calving season. It's a lot of fun. And yes, after a while, the 375 case just doesn't seem that big - Dan

07 March 2002, 05:33

Robgunbuilder

Frankly, I would not recomend a 375 H&HAI. You will gain some velocity, but at a substantial increase in recoil and still never beat a 375 WBY. I have built a number of guns in .375AI as well as various other AI configurations and while I like them, there is the issue that many of the AI reamers out there produce very tight chambers and I've found that there is a tendency for AI cases to stick in the chamber and have to be fulllenghth re- sized every other time or so. Case life will be no better and perhaps slightly shorter. As for barrel erosion, certainly there will be more than in a .375 H&H, but It will be insignificantly more. Of course you can always shoot standard .375's out of it. On the other hand, I've found the accuracy of the AI cartrige line to generally be better than the standard, probably because of the more precise chambers.-Rob

07 March 2002, 06:45

375hnh

OK I'm a little biased here. And I can't add much to what has already been said, except to convey a story. My gunsmith built a rifle as a class project in gunsmithing school. It is an absolutely beautiful 375 built on an enfield action. The only thing is, his teacher talked him into "improving" it. He says he has never regreted anything so much in his life, and if he ever gets time (he's a real good gunsmith), he will change it back to the way it should be. The only way to improve a 375H&H, is to put it in a nicer (better wood) stock.

[This message has been edited by 375hnh (edited 03-06-2002).]