.375H&H Barrel length… what say you?

[TTundra]

And everyone I knew and know that spent time in real combat. Is deaf or nearly deaf.

So true. I have to remind my kids that their grandpa isn't ignoring them...they just need to yell it out louder.

 

[TTundra]

One of our members in a surpressor friendly state needs to get one of these made up for some reviews. Been posted here before, but for your entertainment:

 

[Tug]

One of our members in a surpressor friendly state needs to get one of these made up for some reviews. Been posted here before, but for your entertainment:

It's cool for sure, but I'm quite certain it's not hearing safe

 

[pilar]

Not to mention, they were being thrown out of perfectly good airplanes and hoped their parachutes worked.

If they landed intact, … well, there were Nazis to kill. No suppressors, no ear pro.

View attachment 679357

If you get to experience that once in a lifetime hunt in Africa, forget the can or, worse, the stoopid muzzle break. Just man-up and make your first shot the kill-shot.

Some people need a can on their 375 , because they are sitting in a cement block blind hunting buffalo, I agree if you’re on a OIL free range area after a wild arse old bull , and humping a 10lbs + rifle around all day , a little bit of noise and recoil isn’t really noticeable and probably the last thing on your mind.

 

[Datchew]

And everyone I knew and know that spent time in real combat. Is deaf or nearly deaf.

This.
I was 5 years in a helicopter and an aerial door gunner. Qual'd quarterly in a not so quiet fashion.

Perhaps I'm just soft these days and don't like scary loud noises.

 

[375er]

Not to mention, they were being thrown out of perfectly good airplanes and hoped their parachutes worked.

If they landed intact, … well, there were Nazis to kill. No suppressors, no ear pro.

View attachment 679357

If you get to experience that once in a lifetime hunt in Africa, forget the can or, worse, the stoopid muzzle break. Just man-up and make your first shot the kill-shot.

Now sound off like ya gotta pair!!

 

[skydiver386]

And everyone I knew and know that spent time in real combat. Is deaf or nearly deaf.

If I'd have known I was going to survive all that crap, I'd have worn earplugs.

 

[Sideshow]

Wish they made something that could reduce the report from large bore rifles so they could rely on their hearing in important moments during the hunt… maybe some day!

Well they do have a look at NZ made DPT moderator with muzzle brake included. Here’s the link. https://www.dpt.co.nz/shop/product/799896/suppressor-muzzle-brake-cap-mk2/

 

[Rifleman97]

This was from one of my posts a while ago I shortened my cz550 Inch by inch

Experiment complete .... as non scientific as it may be I did put out the crony and knock an inch off at a time till I stopped at 21" this was my sweet spot for me personally

Honestly I thought I wanted it a inch or two shorter until I shot it a bit and used it and it just feels right so I stopped there

So with factory federal 300g rounds I lost exactly 100fps on several test rounds from 25" to 21" , it averaged 24-25fps on every inch I took off which I'll be honest I thought it would be and increasing curve as length was shortened instead of being equal amounts, not sure why my train of thought I'm just a dumb redneck that lives in the woods but I really thought the shorter I went the more it would lose per each inch and I was wrong!

For those of you that wanted numbers on shorter barrels I appologise I really expected me to like the shorter side of things but the rifle just fits and feels perfect to me I just can't keep whacking away I'm too attached to it now ... I was very very surprised at how exact my numbers were for the rounds used
Several test rounds started at 2599 fps and my ending numbers on 5 shots @ 21" 2 were 2499 exact so I believe it to be pretty justified answer for me on my particular gun ,

yall have a great day and thanks for all the knowldege I know these test have been done before so nothing new here but sometimes you gotta do it yourself and I do appreciate all the help and input

I can actually explain the math on that, the pressure curve in the barrel is very nonlinear up until a certain point. That certain point is decided by the burn rate of powder you are using. After that point, it’s still nonlinear, but it slows by so much it might as well be linear.

With very slow burning powders in heavy overbore magnums, like 6.5-300 wby or especially crazy wildcats like 300 raptor, 7mm Allen Mag, etc you can actually get into the noticeably nonlinear at the 20+ inch mark, just barely.

With the burn rates of 375 hh, the nonlinear area is all the way down in the 0-12 inch mark. After 12 inches, you should gain 35-45fps per inch up to 16-18 inches (varying slightly load to load) and after 16-18 inches it starts only changing 25-35fps per inch, tapering off at 30 inches to about 15-25 fps per inch of barrel.

You can test this in GRT, sure it’s not a perfect simulation of real load data from your actual rifle, but the math checks out extremely well in the barrel length department. If you launch it in the advanced mode, you can see the graph of velocity, and how after a spike it tapers into nearly a straight line at the 12 or so inch mark of velocity gains per inch. Pretty neat stuff. Once you’re past 100% powder burn, it tapers off even more. So longer barrels gain more in the slower powders, but not by as much as you might think.

 

[Jonathan Kashouty]

Go with "23 and have a quality muzzle brake installed. You can then shoot off the bench all day with no concern for recoil.

 

[Rick HOlbert]

I’ve got a BRNO .375 with the factory 25” barrel, plan is to have it cerakoted, synthetic stock & 3 position safety as an all weather rifle.

Question being, for you guys that have had several different barrel lengths of .375’s; what’s your preference on barrel length?

Started with 24in. Had it cut back to 22in. Much handier in heavy brush and with handloads still getting 2500+ FPS with 300grn A-Frames.

 

[deewayne2003]

I can actually explain the math on that, the pressure curve in the barrel is very nonlinear up until a certain point. That certain point is decided by the burn rate of powder you are using. After that point, it’s still nonlinear, but it slows by so much it might as well be linear.

With very slow burning powders in heavy overbore magnums, like 6.5-300 wby or especially crazy wildcats like 300 raptor, 7mm Allen Mag, etc you can actually get into the noticeably nonlinear at the 20+ inch mark, just barely.

With the burn rates of 375 hh, the nonlinear area is all the way down in the 0-12 inch mark. After 12 inches, you should gain 35-45fps per inch up to 16-18 inches (varying slightly load to load) and after 16-18 inches it starts only changing 25-35fps per inch, tapering off at 30 inches to about 15-25 fps per inch of barrel.

You can test this in GRT, sure it’s not a perfect simulation of real load data from your actual rifle, but the math checks out extremely well in the barrel length department. If you launch it in the advanced mode, you can see the graph of velocity, and how after a spike it tapers into nearly a straight line at the 12 or so inch mark of velocity gains per inch. Pretty neat stuff. Once you’re past 100% powder burn, it tapers off even more. So longer barrels gain more in the slower powders, but not by as much as you might think.

Well said sir!

I had a .257Wby that I chronographed with both factory and hand loads @3600fps with its 26” barrel before sending it off and and having the barrel shortened to 24”.

The boomers at the local shooting range literally lost their minds when I told them I was having the barrel cut by 2” and told me to kiss accuracy and velocity good by; their general consensus was that I would lose 100-150fps per inch of barrel cut.

Upon the rifles return, I set up the chronograph and shot both the hand loads and factory loads; as the same brain trust of the local gun range stood behind me giddy with anticipation of being able to say “Told you so”

Results of the chronograph with the same two ammo lots with 24” barrel = 3,550fps

Boomer prediction = 200-300fps loss

Actual results = 50fps loss

So yeah if a .257WBY with RL22 powder only loses 25fps per inch; I’m not worried about velocity loss in a .375H&H

My concerns with barrel length is handling and balance.

Go with "23 and have a quality muzzle brake installed. You can then shoot off the bench all day with no concern for recoil.

22-23” is probably what I’ll do, depending on balance and handling after the new stock is fitted, but god and this forum as my witness….

It will be snowing in hell before I ever desecrate one of my hunting rifles with a muzzle brake!

 

[KJE81]

Well said sir!

I had a .257Wby that I chronographed with both factory and hand loads @3600fps with its 26” barrel before sending it off and and having the barrel shortened to 24”.

The boomers at the local shooting range literally lost their minds when I told them I was having the barrel cut by 2” and told me to kiss accuracy and velocity good by; their general consensus was that I would lose 100-150fps per inch of barrel cut.

Upon the rifles return, I set up the chronograph and shot both the hand loads and factory loads; as the same brain trust of the local gun range stood behind me giddy with anticipation of being able to say “Told you so”

Results of the chronograph with the same two ammo lots with 24” barrel = 3,550fps

Boomer prediction = 200-300fps loss

Actual results = 50fps loss

So yeah if a .257WBY with RL22 powder only loses 25fps per inch; I’m not worried about velocity loss in a .375H&H

My concerns with barrel length is handling and balance.



22-23” is probably what I’ll do, depending on balance and handling after the new stock is fitted, but god and this forum as my witness….

It will be snowing in hell before I ever desecrate one of my hunting rifles with a muzzle brake!

Regarding balance I think it is quite possible to make it balanced regardless of lenght, the barrel on my new .375 H&H which I just recieved today is 65 cm/25,5 inches and still very well balanced on the forward action screw (whats the correct english name for that?).

I guess it might be harder to correct the balace if one wants a shorter barrel then it was originally built with, but if one would like to cut of a couple inches I guess that could be offset by removing wood from the stock under the recoil pad?

 

[deewayne2003]

Regarding balance I think it is quite possible to make it balanced regardless of lenght, the barrel on my new .375 H&H which I just recieved today is 65 cm/25,5 inches and still very well balanced on the forward action screw (whats the correct english name for that?).

I guess it might be harder to correct the balace if one wants a shorter barrel then it was originally built with, but if one would like to cut of a couple inches I guess that could be offset by removing wood from the stock under the recoil pad?

It’s going into a synthetic stock that will be lighter and MUCH smaller size than the factory stock, so I’m thinking it will be front heavy at 25”.

As for “the forward action screw’s” correct English name….. I’ve always referred to it exactly as you said - the forward action screw.

 

[Tam Dl]

One thing that may not be considered about barrel length is that the attenuation, or energy increase on the hearing, is kinda a third order effect. So say you have a rifle where, along with the action, the distance from ear to muzzle is 30 inches. Imagine the barrel is 25" long and you cut it to 20 inches. So the distance to your ear is reduced to 25 inches. The increase in the energy hitting your ear is 44%. Why? Because the attenuation is a second order effect. So it is the square of the first length divided by the square of the second length or 900/625=1.44. As far as I can tell. Accoustics are a little out of my scope. But this part seems simple enough, any engineers out there please demolish my suggestions along this line, if necessary.

But on top of that there is the increase in muzzle blast because of the change in the phenomenon at the muzzle due to the nature of the gasses that emerge there when the sample is taken at different points in the barrel from having trimmed the barrel back. I don't know what that means, it for sure means more. It might be in the range of a third order effect, however that is speculation, it seems as though the effect would be not be linear. But say it was a third order effect it would be 75% more energetic.

The fact something produces more energy does not mean the effects are linear on a biological system. A 6.5mm solid going through JFK's brain would not be more effectively lethal if it hit at a higher velocity than it may have. The threshold of harm in acoustics is often set at 140dB. Magazines I read back in the 70s and 80s said that the dB of various rifles was around 170dB. Which is itself a non-linear increase because the dB scale is logarithmic. So to quote some random physics site: "every increase of 10 dB on the decibel scale is equal to a 10-fold increase in sound pressure level (SPL). Near silence is expressed as 0 dB but a sound measured at 10 dB is actually 10 times louder. If a sound is 20 dB, that's 100 times louder".

But it gets better, I learned 170 DB is actually just what run of the mill dB meters top out at. These magazines were just reporting 170 because the scale didn't go higher. We could be dealing in a range of 300 dB with magnums we just couldn't measure the larger effects with average equipment. We don't encounter those sound levels in normal environments, and if we do, we will loose hearing, several million orders of magnitude before that point. The buzz we hear in our ears after exposure to damaging sound is that nerve ending signing off for ever.

My take away is that the more I have looked into this the more I don't understand. I should have mentioned that earlier. If 140 is the threshold of harm, hearing pro only attenuates 30dB, best case, and magnum reports are in the 300 range, we are all in massive danger near magnums, and brakes. We have manned up to wearing tacky hearing pro, but we are still not looking at the scale of the risk clearly. Small changes in barrel length are non-trivial. In the US is seems somewhat common for guides to ban brakes from camp, but whether that hurts the bottom line significantly I don't know. There are a lot of variables we can control for, but don't, like the effect of various cartridge designs and powers. Consider bow hunting.

Never let your kid take band without hearing pro, and I am talking about non-electric band, let alone anything electric. Drums are lethal.

 

[PCC600]

I own and have owned a lot of big bore bolt action rifles . They all come with original length barrels ranging from 22 to 26 inches . A particular favourite is a CZ550 Safari Classic in 375 H&H with 25 inch barrels . I hunt a lot in scrub and I can honestly say the length of barrel never made a scrap of difference when I had to carry or mount the rifle .

 

[KJE81]

I finally recieved my custom M98 in .375 H&H yesterday after more then 14 months waiting and must say that I really like the proportions that comes from the rather long barrel, 65 cm or about 25½ inches. I realize that it being somewhat unwieldy in the bush is the price I have to pay for that, but still very happy with my choice.

 

[grand veneur]

Nice rifle !

Such rifles are not unwieldy in the bush, unless the length makes the rifle a bit top-heavy, but which is not the case with a rifle caliber 375 H&H Magnum. I have been hunting with rifles with 65cm barrels over thirty years in Africa. The barrel length never bothered me for shooting game.

 

[KJE81]

Nice rifle !

Such rifles are not unwieldy in the bush, unless the length makes the rifle a bit top-heavy, but which is not the case with a rifle caliber 375 H&H Magnum. I have been hunting with rifles with 65cm barrels over thirty years in Africa. The barrel length never bothered me for shooting game.

That nice to hear that from someone with experience of longer barrels in the african bush, I have no experience with the african bush as of yet, only the scandinavian woods and there I find it quite managable, at least with my old 9,3x62 Mauser of similar barrel lenght.

It balances perfectly on the front action screw, so neither front- nor rear heavy. The barrel is of heavier profile then needed for the caliber, but I like the idea of trying to keep muzzle raise as low as possible.

 

[Jack Stevens]

I finally recieved my custom M98 in .375 H&H yesterday after more then 14 months waiting and must say that I really like the proportions that comes from the rather long barrel, 65 cm or about 25½ inches. I realize that it being somewhat unwieldy in the bush is the price I have to pay for that, but still very happy with my choice.

View attachment 680533

Very nice and classy .375. Congrats!