20 vs. 12 gauge for hunting

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Nope, the 410 is a bore measurement as is a 22 shotshell. Gauges are gauges. Calibre's can cover both and is another *******isation of our language.
A 12gauge is not a bore. Never has been in fact only twenty years ago Americans use to take delight in admonishing any Brit using the term bore for a common shotgun guage!
A bore is a measurement usually across the diameter of a tube or circular hole.
A guage uses another measuring method and usually has a wider tolerance in actual measurements often observed for example in 12g by a wide variation in barrel diameters when measured.

"Caliber" originally referred to the length of the barrel measured in bore diameters. 4/18 caliber meant a 4" bore that was 6 ft long.

And gauge refers to the number of bore diameter lead balls to the pound . . . so bore came first. ;-)

Firearms are full of conflicting, contradictory and just oddball naming practices. Part of their charm.
 
I always thought a ‘square load’ was a charge with the same volume of powder and shot....first I’ve heard of ‘tall as is wide’, but then I’m not a born shotgunner.
That's how I learned it as well...though I will admit I've learned some other things wrong in my life. Square load was described to me in my youth as equal parts/volume, heavy was more powder than volume of shot, and light was the inverse. Though, again, I will admit I've been wrong before. Now, at this precise moment I can't remember when that was ;)
 
Thanks for all the replies. Here are my takeaways:

  • 20 gauge might be the better choice for a fowler intended to serve as an all-purpose hunting gun shooting both round ball and shot. (Not really mentioned in this thread but it has been demonstrated that round balls in flight become less stable as the diameter increases, especially without spin).

  • Larger gauges in the order of 10-12 might best be suited to a gun intended to be used exclusively as a "shotgun".

  • As for historical accuracy, it appears that all of the above were used during the first half of the 18th century up through the F&I war. To run this to ground, I aim to get a copy of Grinslade's to examine specific examples.

Final comments or parting shots?
 
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"Caliber" originally referred to the length of the barrel measured in bore diameters. 4/18 caliber meant a 4" bore that was 6 ft long.

And gauge refers to the number of bore diameter lead balls to the pound . . . so bore came first. ;-)

Firearms are full of conflicting, contradictory and just oddball naming practices. Part of their charm.
Re your comments about gauges, there is a flaw.
It is a gauge because it can have variations. One man's pound of lead will have a different volume than another's. One mans pound of lead will display different shrinkage when cast.
A gauge is an approximation. A bore is a precise measurement.
That is why a barrel with 12g stamped on it can be anywhere from .710"-.740" but every 410 I have measured is .410", thus not a gauge but a bore.
To confuse some more, some Europeans call 410's 36call. Go figure but a gauge is gauge and never a bore because you don't get 12 gauges across the bore of a 12g but you measurer the gauge to determine with in a range of choices what your barrel should be close to.
 
Re your comments about gauges, there is a flaw.
It is a gauge because it can have variations. One man's pound of lead will have a different volume than another's. One mans pound of lead will display different shrinkage when cast.
A gauge is an approximation. A bore is a precise measurement.
That is why a barrel with 12g stamped on it can be anywhere from .710"-.740" but every 410 I have measured is .410", thus not a gauge but a bore.
To confuse some more, some Europeans call 410's 36call. Go figure but a gauge is gauge and never a bore because you don't get 12 gauges across the bore of a 12g but you measurer the gauge to determine with in a range of choices what your barrel should be close to.
Just a random thought.... and I can’t prove it but I suspect it. Twelve is an important number. Twelve tribes of Israel 144,000 of the elect(12x12x1000), twelve sacred law tablets of Rome, twelve men on a jury, twelve months in a year ect.
The Bess was made 75-77 cal. I suspect this originally was to let twelve ball to a pound, 72 cal, easily fit in the bore, even though many bess ball was cast smaller, when loaded in a military cartradge.
 
Based on my experiences I think for upland bird shooting/distances, there is more difference in pattern/killing effect induced by the load parameters, and particular barrel differences then by the choice of 20 or 12 Ga. I fully agree with the added versatility of using the round ball in the 62 cal barrel.
 
Biggest difference between a 20 and a 12 gauge is the amount of shot.
 
Just a random thought.... and I can’t prove it but I suspect it. Twelve is an important number.

12 gauge is important due to WW1 and WW2... and this influences our thinking now.

Prior to the the 1st World War, the shotgun bore of choice was 16 gauge, NOT 12. 12 and 10 gauge were waterfowling pieces. Even the United States standard caliber was 14 gauge for muskets, leading up to the ACW..., Not 12 gauge. ;)

But historically..., the 20 gauge hunting fusil was in Canada what the long rifle was in the United States. And for smooth bore, again, the most common in "the states" was the 16 guage, not a 12 gauge or larger, unless you were buying something as a [water]fowler.

LD
 
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I'm going to speak on purely a practical standpoint. I know nothing on which was more common in the 18th century. From what I can tell from the 19th century, the 10 gauge was the all around shotgun gauge up until smokeless powder came about. The 16 is a favorite of mine, but I believe its popularity was more due to the fact that in a SXS, it was much less bulky than a 10, especially in a flintlock.

The difference between the 20 and 12 gauges is that the 12 can send more shot down range effectively. For the most part, a 20 gauge you are looking at about a 3/4 to 1 ounce load for general purpose shooting. I've seen where some have gone as heavy as 1 1/2 ounces of shot. At 1 1/2 ounces, you are not going to have much velocity if shooting a safe powder charge, although it would probably make a good turkey load. A 12 gauge on the other hand can easily handle a 1 1/2 ounce payload with good velocity. It is my opinion that the idea of a square load is a simple way of eliminating having to bring another shot measure. While using equal volumes of shot and powder often produces a good load, I've never found it to be anything special. "Less powder, more lead, shoots farther, kills dead." That's a saying that holds a lot of merit. I'm basing this on both the pattern board and hunting. Shot stringing is another area some look at. I'm not particularly concerned about it as much as some, and in the case of 20 vs 12 gauge, the differences are not as great as you would think. See the following link for tests done by Federal Premium. The Truth About Shotgun Ammo: 6 Questions Answered at Federal's High-Tech Range.

Take note that in 12 gauge, the 3 1/2" load carrying more shot did not have a notable difference in shot string length than the 3". The same is true for the 1 ounce 20 gauge vs 1 ounce 12 gauge. While I realize this is modern shotgun ammunition, the same principles apply to muzzleloaders. You might notice that the 12 gauge patterned tighter than the 20 gauge, but I think this is likely more to do with the particular gun. Change guns, and the results could be swapped.

So what's stopping you from putting 2 ounces of shot in a 20 gauge? Velocity, at least from a fowler barrel. To use such a heavy payload, would require a low amount of powder to keep things safe. The result would be pathetic velocity. The 12 gauge on the other hand could handle a 2 ounce payload, although it is getting to be about topped out there. My Pedersoli 10 gauge, is in reality an 11 gauge. With 2 ounces of shot, and 100 grains of powder, velocity is 900 fps at the muzzle. That load worked great on turkeys, and would work on flying birds too, but it is getting on the slow side.

The other factor is choke, which is a post civil war invention. To remain truely PC, would require a cylinder bore. That Pedersoli I mentioned is a cylinder bore in both barrels, and let me say that I needed all the shot I could get for turkeys. I ended up shooting my turkey real close at about 10 yards, so anything would have worked. If it hadn't though, my maximum range was 25 yards, and not one yard past that. I really doubt you are going to be able to get an effective turkey hunting pattern from a cylinder bore 20 gauge at that, and even 20 yards might be pushing it. As a wing gun though, you don't need nearly the same pattern, and a 20 would be quite effective in that role.

The only real drawback to the 12 is weight and bulk. In a single barreled fowler, the bulk wouldn't really be a factor either. I'd say go for the 12 gauge, and wouldn't discount a 10 either.
 
I'm going to speak on purely a practical standpoint. I know nothing on which was more common in the 18th century. From what I can tell from the 19th century, the 10 gauge was the all around shotgun gauge up until smokeless powder came about. The 16 is a favorite of mine, but I believe its popularity was more due to the fact that in a SXS, it was much less bulky than a 10, especially in a flintlock.

The difference between the 20 and 12 gauges is that the 12 can send more shot down range effectively. For the most part, a 20 gauge you are looking at about a 3/4 to 1 ounce load for general purpose shooting. I've seen where some have gone as heavy as 1 1/2 ounces of shot. At 1 1/2 ounces, you are not going to have much velocity if shooting a safe powder charge, although it would probably make a good turkey load. A 12 gauge on the other hand can easily handle a 1 1/2 ounce payload with good velocity. It is my opinion that the idea of a square load is a simple way of eliminating having to bring another shot measure. While using equal volumes of shot and powder often produces a good load, I've never found it to be anything special. "Less powder, more lead, shoots farther, kills dead." That's a saying that holds a lot of merit. I'm basing this on both the pattern board and hunting. Shot stringing is another area some look at. I'm not particularly concerned about it as much as some, and in the case of 20 vs 12 gauge, the differences are not as great as you would think. See the following link for tests done by Federal Premium. The Truth About Shotgun Ammo: 6 Questions Answered at Federal's High-Tech Range.

Take note that in 12 gauge, the 3 1/2" load carrying more shot did not have a notable difference in shot string length than the 3". The same is true for the 1 ounce 20 gauge vs 1 ounce 12 gauge. While I realize this is modern shotgun ammunition, the same principles apply to muzzleloaders. You might notice that the 12 gauge patterned tighter than the 20 gauge, but I think this is likely more to do with the particular gun. Change guns, and the results could be swapped.

So what's stopping you from putting 2 ounces of shot in a 20 gauge? Velocity, at least from a fowler barrel. To use such a heavy payload, would require a low amount of powder to keep things safe. The result would be pathetic velocity. The 12 gauge on the other hand could handle a 2 ounce payload, although it is getting to be about topped out there. My Pedersoli 10 gauge, is in reality an 11 gauge. With 2 ounces of shot, and 100 grains of powder, velocity is 900 fps at the muzzle. That load worked great on turkeys, and would work on flying birds too, but it is getting on the slow side.

The other factor is choke, which is a post civil war invention. To remain truely PC, would require a cylinder bore. That Pedersoli I mentioned is a cylinder bore in both barrels, and let me say that I needed all the shot I could get for turkeys. I ended up shooting my turkey real close at about 10 yards, so anything would have worked. If it hadn't though, my maximum range was 25 yards, and not one yard past that. I really doubt you are going to be able to get an effective turkey hunting pattern from a cylinder bore 20 gauge at that, and even 20 yards might be pushing it. As a wing gun though, you don't need nearly the same pattern, and a 20 would be quite effective in that role.

The only real drawback to the 12 is weight and bulk. In a single barreled fowler, the bulk wouldn't really be a factor either. I'd say go for the 12 gauge, and wouldn't discount a 10 either.
Never had a velocity issue with my 20g with standard 12g loads. I don't do fairy powder charges either and never thought I was not being safe!

In the past twenty years there has been a trend for cartridge ammunition to get lighter and lighter loads. Many an option for 7/8oz loads exist for 12g!
It's just popular choice, there is no rhyme or reason to it. " Yeah I got the 12 instead of the 20".
"Really, why Bubba".
"Well, cousin Jo says it's better so.....".

How is it better?(don't answer).
How many times has shot bounced off a critter from a 20g?
How many less pellets have you had to pick out of meat from using a 20g, or how many more pellets have you picked out using a 12g?
It's all jibba jabba nonsense.
 
Nope, the 410 is a bore measurement as is a 22 shotshell.
That's what I said.

Historically, a "12 gauge" takes 12 bore diameter balls to equal 1 pound.
A "20 gauge" takes 20 bore diameter balls to reack the same weight.
A "16" guage" takes 16 balls, a "10 guage" needs 10, a "4 gauge" only needed 4 balls.

There were no mechanical/physical gauges used to determine the gauge. The bore diameter could, and did, vary slightly (thousandth's of an inch) between manufacturers.

Once past "gauge" and you reached "bore" territory (if memory serves the largest "gauge" was 4 gauge. Anything larger than 4 gauge was a "bore".)
things changed.

I do remember the higher the bore number (eg "1 bore" vs "2 bore") the larger the bore diameter. The reverse of "gauge" bore diameters.

So, no. A "12 bore" and "12 gauge" are not the same thing.
A "12 bore" is a canon.
 
That's what I said.

Historically, a "12 gauge" takes 12 bore diameter balls to equal 1 pound.
A "20 gauge" takes 20 bore diameter balls to reack the same weight.
A "16" guage" takes 16 balls, a "10 guage" needs 10, a "4 gauge" only needed 4 balls.

There were no mechanical/physical gauges used to determine the gauge. The bore diameter could, and did, vary slightly (thousandth's of an inch) between manufacturers.

Once past "gauge" and you reached "bore" territory (if memory serves the largest "gauge" was 4 gauge. Anything larger than 4 gauge was a "bore".)
things changed.

I do remember the higher the bore number (eg "1 bore" vs "2 bore") the larger the bore diameter. The reverse of "gauge" bore diameters.

So, no. A "12 bore" and "12 gauge" are not the same thing.
A "12 bore" is a canon.

That's not true, a 12 bore and 12 gauge are exactly the same thing. They even still use bore over in the UK, while the USA mostly uses gauge. They are different words that mean the exact same thing. A 4 bore is way bigger than a 12 gauge.
 
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