Big Bore - Caliber vs. Gun Size...

[Encore64]

After spending a week developing loads for the BFR 357 Magnum, I started to question what I knew...or thought I knew.

The 357 Magnum is definitely a small bore in the massive BFR. But, often thought of as a medium bore in other guns.

The 10mm is no cannon, but definitely a big bore in a Single Six.

I don't really consider the 45 Colt a big bore, though most do. In a SAA or Flattop Midframe, it's definitely a big bore.

But, put it or the 454 Casull in a BFR and it seems more medium bore.

So, is bore nomenclature definitely by size or relative to the gun it's chambered?

[bushog]

I would say it's defined by the size of the hole.

Big Bore > .45 in my book....

A big cartridge in a little revolver is a "handful".

[silcott]

Big bore starts at 45 for me.

[edk]

Always considered the 44 & 45 big bore. If one were to say big bore is over 45, then practically speaking, no big bore revolvers existed over 30-40 years ago.

[Encore64]

Feb 25, 2024 20:17:49 GMT -5 silcott said:

Big bore starts at 45 for me.

It's the pivot point for me too. I just never can decide which side of the line to put it on.

Definitely a big bore in my two FA97s in 45 Colt...

[bigbrowndog]

I do not take gun size into consideration when determining whether it is a big, medium, or small bore.

Trapr

[pleadthe2nd]

I think it starts at 4 for big bore, a 40 in a semi-auto seems big bore to me, even 41 in a revolver, regardless of the size of a certain model, since there are different models, by different manufacturers for most calibers available, but that's just my take, currently my big bores stop at 45

[drycreek]

Interesting. I guess I never thought about bore size relative to gun size but it’s definitely something to consider. A .357 in a snub is not only a screamer, but it’s a hand full, especially in a lightweight frame. The first .41 mag I ever owned was a Blackhawk with a 4.6” barrel, and hot handloads felt right up there with factory .44s in a 7.5” barrel, especially with the plowhandle grip. I can’t tell much difference in hot .44s and Ruger only .45s in the same size gun. I guess for me, “big bore” starts at .429.

[singleaction]

I consider 44 cal as the start for big bores in a revolver. However, I guess I tend to delineate what might be considered to be modern big bores as using significantly heavier bullet weights and/or faster velocities than what is generally considered to be traditional. In my small mind, big bores start with mid-range 44 special. I reckon 41 mag should be considered a big bore, in my world, given its closeness in diameter to 44, but certainly not 41 special. How’s that for flawless logic!

[potatojudge]

Big bore in a bottle neck rifle round starts smaller than 45 for sure.

[sixshot]

Interesting question, never really thought about it the way you've worded it but I'd have to say it would depend on if the caliber was loaded to it's full potential. If that's the case then I would include the 41 magnum & go up from there. Any of the magnums can be loaded down but the case head is still stamped "magnum". Many of my 44 magnum loads are only 10 grs of Unique with a good cast bullet, not much of a magnum load really. Hope that makes sense.

Dick

[Encore64]

It just struck me as odd late last week. I was accuracy testing the BFR 357 Magnum when a friend texted me pictures. Half way across the country, he was doing the same with his SP101 357 Magnum.

Same cartridge, but two guns obviously built with different purposes in mind. Some will argue with anything, but figure most will agree that a BFR 8.2" Barrel is not ideal for concealed carry.

[marcruger]

My opinion would be that "big bore" has nothing to do with gun size. If that were the case a NAA mini-revolver shooting .22 short would be big bore.

In my mind Big Bore starts at .44 Caliber, but I struggle with .41 Magnum. A hot .41 is way more powerful than a standard .44 Special, so I think there is room for waffling there.

God bless, and best wishes, Marc

[CraigC]

This isn't something that keeps me up at night but to me, "big bore" has nothing to do with performance or the size of the gun. Anything .40cal and over is a "big bore", which seems to apply equally to rifles.

[AxeHandle]

no big bore revolvers existed over 30-40 years ago. 1984-1994?
Big bore to me is 41 and up. Size of the gun isn't a part of my personal equation. My 5 shot 22 Hornet? Small bore. 22 Hornet Ruger Super Redhawk? Small bore. My 5 shot Charter Arms Pit Bull 45 ACP? Big Bore! 45-70 Bond Arms Deringer? Big Bore!