What exactly is a "Big Bore" rifle?

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Good morning all,

I was reading over some of the recent threads on here and it suddenly occurred to me that I had a very poor grasp on what, exactly, a "Big Bore" rifle is. I know the "Wikipedia definition" which is "large-bore refers to calibers with a diameter of .40 inches or larger." but what does that mean to you? For example when I decided to go to Africa for the first time last year I purchased a .375 H&H. Having never shot anything (in the civilian world, not counting the service) larger than a 300 Win Mag the .375 was most definitely a "Big Bore" to me! I thought that surly the minimum caliber acceptable to stop an elephant must be a big bore, but by the definition I was mistaken. I then purchased a 404 Jeffrey. Now I certainly had the "text book" big bore, but I have come to find that some do not even consider this, nor the 416 that would come after it, to be a "big bore" rifle. So I'm asking the community: What, to you, is a "big bore" and why? Is it bullet weight? Speed? Recoil? Sheer machismo and history? Please let myself and the others who may be wondering but do not want to ask know. As always, thank you in advance for your time and wisdom.
 
I think it depends on who you talk to...

Most would tell you that anything .375 or larger constitutes "big bore"..

Many others would tell you that "big bores" start at .40 however .. and that nothing smaller meets the requirements..

I dont think recoil or even the delivery of kinetic energy is considered by most people.... I havent met anyone that would argue that a .45-70 isnt a "big bore".. but clearly the .45-70 delivers pretty weak sauce when considered side by side with a .375 H&H, which some consider a very big "mid bore"...
 
Depends on the times, in the past big bore was 45 caliber and up, 375 to 45 was medium bore. Times have changed some now say 40 caliber and up, some say 375 and up. I wouldn’t worry to much about it, buy a rifle that is legal to use on the animals you are hunting, and learn to shoot it well. As a hunter you need to place your shot where it does the most good. Your PH needs to worry about the stopping power.
 
To me it depends on whose hands the rifle is in ie a hunter can consider a 375 to be a light big bore or a 416 a medium big bore now when the hunter gets to 458 and 5500 fp of energy [plus]they are in the game. Now a PH may consider a 416 adequate for stopping right now but many start at 458 and go up from there 505 Gibbs 500 Jeff 500 nitro in a double.
So in the eyes of the beholder says it for me as to what is”BIG BORE”
 
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Own a .375 HH and I’m of the opinion a big bore is in the .40 bore.

I’d love a .404 Jeffery and wanted one for year and years. Though being Canadian a .458 is more practical with the selection and quantity of .458 bullets up here.

With that reason to, I dream of a .450 NE double. It’s the perfect combination to me
 
As far as I'm concerned a big bore is .375 and upwards.
If that is the minimum legal calibre to use on the largest land animal that will be my definition.
Sure it might not be correct for the purists, pedants and calibre geeks but it's my opinion and I'm sticking to it.
You can ask ten different folk and get ten different answers but that is mine.
 
I would not consider a 40 muzzleloader a "big bore" hence my centerfire comment.

you are correct, for muzzle loaders its basically 30-50 caliber for small bore. then you have 50-80 caliber for medium bores and 80+ caliber for large bores.

As far as I'm concerned a big bore is .375 and upwards.
If that is the minimum legal calibre to use on the largest land animal that will be my definition.
Sure it might not be correct for the purists, pedants and calibre geeks but it's my opinion and I'm sticking to it.
You can ask ten different folk and get ten different answers but that is mine.

so if RSA made the .22 caliber legal for elephant then you would say the .22 is a large bore? African politics should have no bearing on the definition of the term "large bore".

i think the traditional terms are fine, whats wrong with calling the 375 and 416 caliber medium bores? calling them medium bore cartridges does not reduce their effectiveness on game. large bore smokeless cartridges start at .458 and tend to be very specialized cartridges designed for only the largest game usually at short range. medium bore cartridges run from around .350-.440 (these arent exact but im too lazy to look it up) and tend to be more of "jack of all trades" cartridges suitable for both medium and large game including dangerous game.

i use my 416 RM primarily as a PG rifle firing a 300gr bullet at 2700fps. the benefit to this is that if there is a problem with my large bore rifle on a DG hunt then the 416 can pull double duty and be used for dangerous game as well. i dont believe in "one gun safaris" and from personal experience would always recommend bringing two guns that are both capable of performing the same role.

-matt
 
so if RSA made the .22 caliber legal for elephant then you would say the .22 is a large bore? African politics should have no bearing on the definition of the term "large bore".

I think that's a little extreme and we both know it will never happen so the point isn't well made.

The OP asked the question and I answered with my opinion and definition. I didn't say it was correct and everyone should think the same way as me, in fact I mentioned that ten different hunters would likely have ten different opinions as you have demonstrated.

Many here might question using a .416 for plains game but no one should tell you you're wrong if that's your choice. In fact I would suggest you're in the minority but if it works for you then fair play, I'm not going to tell you you're wrong.

Agree to disagree, accept others have different opinions.
 
From memory Pondor Taylor in African Rifles and Cartridges has Big Bores as .45" and bigger, .40" to.44" as Large Medium bores, .375" is the top end of Medium Bores (can't remember the lower end).
 
matt,
you make a good point.
if your bigger rifle will put its heavy bullet dead on at 100, AND a lighter bullet 2" to 3" high at 100, you have a versatile setup that can handle big stuff in close and smaller stuff out further as the case might demand.
the 375 h&h will do this, but i have never used a 40 cal.
when the 577/450 was adopted it was considered and referred to as a smallbore, and was relative to the more common up to then 577.
45 in black powder was an express deer rifle, with some preferring 40 cal for the same job.
smokeless powder altered killing power immenseley, turning 45 cal into an elephant killer.
366, 375, and 40, became medium bores, for their ability to take quite large game as well as smaller species, anfd 45 became the bottom end of large bore.
it would seem that true large bores do not have the longer point blank range of the mediums.
bruce.
 
I must agree with the consensus here...it depends.

It was correctly (I think) pointed out that a .40 cal muzzle loader is not a big bore.

For centerfire rifles I consider big bore to start at .45....and if really backed into a corner, I might even say .470.

I consider my 450/400 as definitely a medium bore.

I have a buddy who is from the Les Bowman school. He thinks .30 cal is big bore!
 
I am all for the medium bore 375 being legal for people to shoot at the big stuff. If they didn't many people would not ever be able get a cape.

"For me" it's a great round for PG and leopards and lions with a kicked in the ass load with bullets that create one hell of a lot of damage. Please don't go after a kitty with an expanding round that you would use on a cape. Do I .like it for stuff that wants to have it's way with me by a mushin and a squishin? Oh god no (and you pick the god of your choice).

For me I am truly a firm believer that the 458 win mag should be the absolute minimum to shoot all of the "Big 5".

Wanna shoot a leopard? Who doesn't? Right?

It makes me cringe when I hear someone say, " yep! that 270 is more than enough for a leopard " Sure! It may weight what a deer does, but as of today I have never seen a deer with claws and fangs that will go out of it's way to pick a fight with you and consider nothing less than your death as a way of settling the dispute.

I have what I consider to be " enough " for a kitty cat that will attack and peel your bwanna guts out of you and won't care that there are 6 other people standing around watching you getting torn to shreads. It's a good old 458 Winchester magnum loaded to screaming velocity with a thin jacketed 350 gr round nosed bullet. Unleash that dog off the chain right through Kitty's heart and lungs at 20 yards and you don't need to go looking for him in the dark....he's dead right where you shot him.

Many here seem to " romanticize " the use of rounds that were used in the past to exterminate much of game that once covered Africa. How many times is it mentioned a guys name and that he shot thousands of elephants with a 7mm?

If there was no laws now, just like there were no laws then I wonder just how many limping animals would be getting sized up by vultures and how many bwannas would be " what's for dinner" tonight?

I forget who said it here, but I will always tip my hat to the guy who wrote, " and when you hit something and it goes down keep shooting it so it never gets up...it isn't like you get to take the meat home anyway". Oh my! That man knows the truth. I have see guys write that it's the pH's job to stop the animal so he needs the big stuff.

I completely disagree and should I ever feel that way I would never hunt or shoot ever again. My sense of accomplishment comes from what I can do to take an animal down with one shot, not to wound it and expect someone else to stop it from stomping or clawing me to death.

My last hunt on the continent has been quite a while ago, but I still remember my talk with the ph. Whereas it was his job to find me game and make sure I came back in one piece it was my duty to kill my game .,,.not his. He was a fine pH, a good man and he would be over 60 today. We conversed for some years and then he disappeared.

So what really is a "Big Bore Rifle"? To me it's something that has a personality like a sun baked Missouri mule who's made to pull a plow after quitting time and will drop and stop anything with one shot on a continent where the animals have done what is necessary to survive from day one of their life in an unforgiving land.
 
The term " big bore," only has to do with bullet diameter.

40 caliber and up.

So it has nothing to do with the operator??????? :W A Rifle: :W Sharp Shooter: :E Happy:
 
von s,
romanticising rounds can be a serious downfall as you say.
the 318 W.R. had a good name for game up to a certain size.
it got a bad name from people then oversesimating its capabilities based on that, and then getting killed by bigger or more dangerous game.
this is not to condemn the cartridge in any way, but rather its choice for game beyond its capability.
a lot of non dangerous game suffers for the same reason, but people keep doing that because a) it does no cause the shooter to suffer pain like it does the animal and b) the animals do not pose a risk when wounded.
dangerous or non dangerous game, we owe them a quick death equally - a moral responsibility.
it is not their choice that we elect to shoot them.
refusal to romanticise a cartridge is a step in the right direction.
bruce.
 
You know Bruce?

If we ever meet I will tip my hat and shake your hand.
 
My vote is:
40 cal = mid bore
45 cal (.458) + = big bore.
 
Would also depend on what you are hunting and not only bullet/bore diameter.

Old time Professional Hunters classified calibers for use on elephant as below .400 as small bore, above .400 and below .475 as medium bore and above .475 as large bore.

Bear in mind this is for DG hunting and specifically for elephant hunting and from a Professional Hunters point of view.

Today this would probably be anything below .375 as light, .375 up to below .458 as medium bore and then anything over .458 as large bore, bearing in mind that far fewer elephant are hunted today than back in the day and that bullet technology and performance have enhanced the ability of the different calibers on DG.
 

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