What do you call a big bore?

Casull

Casull

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Okay, there are a few big bore fanatics out there. Through different times and in different places the definition of what a big bore is has changed.
I have read of the great old days in Africa before smokeless powder when big bores were 8 bore and 4 bore rifles and the .577 and .500s were mid bores and 45 and under small bore rifles.
Then seems to be the era of smokeless in africa when .577s and .600s were big bores and .500s and the like were the average mid bore.
Now with bullet advances and less hunters having to take on dangerous animals by themselves, these large guns are all but gone and .45 rifles seem to be big bores.
This makes me think of the old days of NA game when .50/70s, .50 Sharps, .577 Sniders and so on were used on heavy animals and the .45/70 came to fame.
Nowadays, what do we all consider big bore, mid bores and so on? My definitions I guess are small bores being anything under about .284" or 7mm. Mid bores from there up to .400" and big bores on from there up with some other classification for .500" plus rifles as stoppers or extra heavy rifles or something.
There are obviously short pistol and carbine rounds with large diameters and low speeds that really only partially make it into the big bore realm like the .44/40 and so on. But the .500 S&W in a carbine would be something to qualify by most definitions. Some consider a .375 H&H a big bore, to others it's a mid bore.
I have had a lot of experience with many big bore rifles and handguns over the past 20 years or so for no other good reason than they interest me.
How do you guys catagorize these things and what big rifles are you using?
 
For me the split between small and mid would be around 6.5mm to 270 cal, mid to large around 35 cal. Pretty irrelevant definitions though in my oppinion. Is a 270 Win a worse choice for deer to moose sized game than say a 35 Rem?
 
Casull said:
What is a .700 T-Rex? I have not heard of that.
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Go to accuratereloading.com and get into the humor section [videos] Then take a look at some of those poor schmucks shooting that 577 T-Rex. It will be good for a few chuckles, to be sure. Regards, Eagleye.
 
I have seen those videos, they are great. Bevan King has made some .585 Nyatis on P14 actions. I think that is the .577 Nitro modified to be fired from bolt guns and loaded to higher pressures. Ballistics seem to be 750 grain bullets up to about 2450 fps. I have a P14 that takes a .577 Nitro case necked up to .600(.620") bullets. I have not used it enough yet to say much about it. These are something beyond the standard big bore though.
 
I consider a Big Bore to be over 40 cal, and housed in a "larger than average" (whatever that means) cartrigde.

So a 458 WM is a big bore, so is a 416 Rigby, but a 444 or 45/70 is not.
 
For rifles I'd say over .40, 400 hundred grains and about 5000 foot pounds of energy. The line gets a little blurry around the .375s. I'd put the medium bore lines at .338 to .375, with the .375s H&H and cousins being "Heavy Mediums". 8mm or .323 and down are small bores no matter how big the case is.
Velocity and bullet weight have to play a part, or a 44/40 would be a "big-bore" instead of a pop-gun.
 
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For me it goes as follows:

Big bore: .400 and above

Medium bore: 375 H&H and 9.3x62 Mauser.

Light medium: .308 to .375

Light: Below .308

I do belive that the 375 H&H and 9.3x62 Mauser belong as a class of their own. Any hunter should be able to handle these cartridges and you can hunt the world with them with confidence of being able to handle any game in the world.
 
Dogleg said:
For rifles I'd say over .40, 400 hundred grains and about 5000 foot pounds of energy. The line gets a little blurry around the .375s. I'd put the medium bore lines at .338 to .375, with the .375s H&H and cousins being "Heavy Mediums". 8mm or .323 and down are small bores no matter how big the case is.
Velocity and bullet weight have to play a part, or a 44/40 would be a "big-bore" instead of a pop-gun.
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I will go with this guy and Gatehouse. It is a combo of the caliber as well as the "power" behind the projectile.

Noel
 
Casull said:
What is a .700 T-Rex? I have not heard of that.
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Come to think of it niether have I..............:redface: :p

I was Actually thinking of the 700 Nitro but had the .577 Tyranosaur on the Brain too ;)

I read the .700 Nitro produces some 12,000 ft lbs of energy.

Might be Marginal for deer:dancingbanana:
 
To my way of thinking .30 and under are small bores, medium bores are from .8mm to .458, but .458 and larger are big bores. Sorry guys - but there's just been too many references to the .416 Rigby being a medium. Energy figuers of 5000 ft. lbs would seem like a good way to keep pistol cartridges out of the big bore criteria, but I suppose we could just as easily use a minimum of 500 grs at 2000 fps.
 
I suppose that intended use and by whom could be considered. Most African dangerous game caliber rules are framed for .40 and overs with the .375 being let in under the wire. Stopping rifles on the other hand really do start at .45 cal, 500 grains and 2000 fps. Even the 458 Winchester is viewed with suspicion, so you could put the line there for stopping rifles for a PH. The Lott is getting real popular, partly because there are a few affordable and quality rifles available for it.
 
Boomer said:
To my way of thinking .30 and under are small bores, medium bores are from .8mm to .458, but .458 and larger are big bores. Sorry guys - but there's just been too many references to the .416 Rigby being a medium. Energy figuers of 5000 ft. lbs would seem like a good way to keep pistol cartridges out of the big bore criteria, but I suppose we could just as easily use a minimum of 500 grs at 2000 fps.
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What you're getting at is more in line with cartridge or caliber power. To me, big bore means exactly that, bore diameter, be it handgun or rifle. My 500 S&W, while it admittedly, doesn't have the power of many rifle cartridges, it is still a big bore. A bit of a side issue, but according to Mark Hampton of The American Handgunner in his article, "To Africa With A .500 S&W", the gun proved up to the task.
 
For commonly used North American cartridges (not including the big African "stoppers") my take on it is thus:
.17 - .308 = small bore
.338 - .375 = medium bore
.40 & over = big bore

For those who haven't tried it, a .45-70 loaded to medium pressures (lever gun loads) and utilizing 400gr+ hardcast bullets is most definately a big bore and has proven it's capability to down any game animal on this continent within reasonable range (and happens to one of my pet cartridges to load for ;) )
 
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