10MM or 357 mag

While this would be interesting it would also be of use only to those intending to compare the two rounds directly in very similar platforms.
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A quick search on this board, or elsewhere across the 'Net, would tell you that the ".357 Mag revolver v 10mm autoloader" debate is the most recurring one that exists. Seen it many, many times over the years here, over on GT, on THR, on AR15.com, etc.

That's why an apples-to-apples comparison of these cartridges, using the same platform, would make sense toward resolving the issue - it's by far the most popular among inquiring minds who want to know accurate details about fun and useful stuff .. . ;)
 
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Well, I own multiple .357s and decided to get a 10MM 1911 when I read about a black bear sighting about 50 miles away. It's more concealable when I urban carry for bear defense. :)
 
Hmm, have both, love both.

If I had to choose just one I think I would keep my .357s. I couldn't bear parting with 90% of my revolvers and I have other 1911s in 45.
 
When comparing barrel lengths between an autoloader and a revolver it's not the same. Say you have a 4" barrel in an autoloader and a 4" barrel on a revolver they're not the same.

It comes to "speaking length" of the 4" barrel which is from the bottom of the bullet to the end of the muzzle. In an autoloader the casing takes up some of the barrel and in the revolver the bullet is inside the cylinder so you can add about 1/2" to the speaking length of the 4" barrel.
 
It's hard to figure why revolver barrels are measured differently than most firearms, which is breech-face to muzzle.

When comparing ballistics, this would be the way to measure, although it could cause confusion when discussing other aspects.

As mentioned above, a 4" revolver (as typically measured) is considerably larger overall than a typical 5" semi-auto. The commonly used specs are misleading for purposes other than comparing revolvers to other revolvers.
 
chronograph test pitting a 357 Coonan autoloader against any 10mm autoloader having the same length barrel, ... and see whose outcomes win the velocity/energy tests.
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This would give you a general idea, but isn't definitive for every situation. Using a Contender with barrels for each caliber would be the same, a general idea, but since barrels vary, one would need multiple examples to be certain the velocities weren't just flukes. 50fps or more, (even 100fps is not unknown) difference between the same length barrels shooting the same ammunition happens. If either of your test guns happens to be unusually fast, or slow, it could give you a misleading result.

It's hard to figure why revolver barrels are measured differently than most firearms, which is breech-face to muzzle.
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It might be because that is the actual length of the barrel. ;)

It comes to "speaking length" of the 4" barrel which is from the bottom of the bullet to the end of the muzzle. In an autoloader the casing takes up some of the barrel and in the revolver the bullet is inside the cylinder so you can add about 1/2" to the speaking length of the 4" barrel.
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I understand how you are measuring, but am uncertain what you are saying. Are you saying we should add 1/2" to the revolver barrel length as "speaking length" over the auto pistol barrel length?

because, if you do, shouldn't you also subtract case length from the speaking length of the autopistol barrel??

A revolver barrel is nominally what ever length it is, 4", 6", etc., from one end to the other. That is the length of the rifled tube.

A semi auto pistol barrel can be the same overall length but, it includes the chamber, so the length of the rifled tube is shorter than it is in the same length revolver barrel, by the length of the loaded round, approximately.

The .357 Magnum has a max SAAMI spec length of 1.590, the 10mm 1.250".

If you are adding a half inch (as the approximate distance from the base of the bullet to the rifling) in a revolver shouldn't you also subtract the approximate inch (.357)or 3/4" (10mm) taken up by the case in an autopistol barrel to make the "speaking length" of both?

And I don't see where the "speaking length" is making any allowance for the barrel/cylinder gap of a revolver. Could you explain further, please??
 
That's just a guesstimate but you get my point.

To make it fair, the barrel length of a revolver should include the cylinder chamber just like the chamber/barrel of a autoloader.
 
It might be because that is the actual length of the barrel. ;)
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Yeah, you got me there.

I'm thinking of it in terms of standardization for comparison to different types of firearms but that is not the intent of the manufacturer's description. I doubt we're going to upset a long history of describing revolver barrels as we do and it would cause a lot of confusion if we did.

It's not difficult to use the entire "length under pressure" for comparing ballistics and handling qualities if we so wish, with the acknowledgement that this is not the literal, but rather the functional barrel length.

Accounting for the cylinder gap is a tough one. We'll never have a usable apples to apples comparison between revolvers and semi-autos in every respect but we can come a lot closer than using the catalog barrel dimensions.
 
Accounting for the cylinder gap is a tough one. We'll never have a usable apples to apples comparison between revolvers and semi-autos in every respect but we can come a lot closer than using the catalog barrel dimensions.
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You're probably right, but what else do we have but the listed barrel lengths?

Comparing different guns and different loads in gun with the SAME listed barrel length produces differing results, even when the barrels actually ARE the same length, so I wouldn't sweat it much.

People will claim the superiority of their favored round (or load) if they get a handful of FPS faster than the "competition", and the reality is, that velocity advantage can disappear with a different gun, or even a different bullet in the same gun.

Here's an example of what is possible (its not the usual, but it happens enough to not be a freak occurrence)

A hot 125gr .357 load (2400 powder) chronographed from three different guns with nominal 6" barrels. A S&W M19, a S&W M28, and a Desert Eagle.

M19: 1620fps
M28: 1670fps
DE: 1720fps

The DE turned in the highest speed, despite the fact that the actual DE barrel includes the chamber. Also, the DE barrel used was polygonal rifled. SO, somehow, despite a shorter "effective" length, the polygonal rifling and no cylinder gap turned in the highest velocity.

Now, do note the 50fps difference between the two different revolvers, both with 6" barrels, so the difference there is strictly the difference between two essentially "identical" barrels.

The point here is that barrels the same length, measured the same way, shooting the same ammo, turn in different velocities. Most of the time its only a handful of fps variation, but sometimes, its considerably more, and this is NORMAL.

In other words, the guy who claims his choice is superior because his gun and load clock 37 fps more than yours, or more than a quoted book speed is blowing powder smoke up your ...nose...:D
 
Having had two 4 inch revolvers of the same make and type with serial numbers that were less than 20 apart and firing identical loads through both guns over a chronograph I got 150 fps difference in average velocity between them.
Just the internal dimensions of the barrel and its finish was the only difference between the two revolvers. When you start trying to compare the velocities of ammo between pistols you will run into the same variations. That is why we have chronographs... so we know the actual velocity of our bullets. If you don't measure you are guessing.
 
You're probably right, but what else do we have but the listed barrel lengths?
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Well, for the purpose of comparing different handgun types, I think a very practical first step is to use "length under pressure" or "effective barrel length" as opposed to literal barrel length of revolvers. Then perhaps apply a rule of thumb factor to account for cylinder gap. That is what I would call a usable formula for informal comparison. Not exact but better than taking the catalog lengths literally.

A less usable, but likely more accurate formula would include a gazillion dimensions, pressures etc. Just identifying the factors could be a major job, depending how far you want to take it. And as your example implies, there are probably subtle factors that we would struggle to quantify. Polygonal rifling for instance. I think you'd just have to isolate the variable, do a lot of shooting, then average out the results to come up with an approximate correction factor. It would take a lot of time and resources.

I'll have to settle for the short form version. :D
 
Sure, but the question here is how much gun sizewise will it generally take (in different platforms and calibers) to get that velocity and power. If you mean use a chronograph to get a general idea of the relationship, that would work if you use enough samples. There will be a velocity range even among "identical" guns as you and 44AMP have said.

My 5" .40 will push a 155gr JHP a little over 1300fps which is a hair under 600fpe. This is with standard pressure loads from powder manufacturers and I still haven't been to the max with Power Pistol. A 10mm surely has even more potential.

Given enough barrel, a .357 will outdo this but at that point, you are talking about a different sort of gun. A 5" semi-auto is packable. Sizewise, it is about like a 3 to 3-1/2" revolver. That is what I am getting at and what you don't see when concentrating on advertised ballistics and literal revolver barrel length.

My GP-100 has a 6" barrel by the way. I like it a lot for its intended purpose. The length and sight radius are actually a plus there. I'd rather not try to CC the thing though. Even open carry would be somewhat of a pain.
 
Random guy,
A 6 inch Ruger is not difficult to carry at all. I've done it for 45 years. I have carried it in a custom pancake holster and a shoulder rig. It is easier to access in a shoulder rig, especially when seated or driving a car. I have carried it in a western style holster when back packing too.
 
Its funny, how attitudes and opinions change over time. Those "old guys" who were writing about guns in the 50s, 60, & 70s were all pretty uniform in their opinions about packing/concealing a revolver.

And that was that the bulk of a revolver is in the frame/cylinder and the grips, and the barrel length didn't make as much difference in concealing the revolver, until you go significantly beyond 6".
 
10mm...

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If Coonan does an extended magazine like that, then I'll reevaluate.

Seriously, I'm not a .357 Magnum fan. .44 Magnum, hell yeah! .38 Special, ok... even though I converted my 642-1 to 9mm. It's just the power increase to .357 Magnum isn't worth the differences in shooting it compared to the .38. With the .44s, I feel the increase is worth it.

Both work. One is predominately a revolver cartridge, and the other is bigger in semi-autos. Neither will leave you peeing into the wind...
 
The Coonan Classic mag can't get much longer because of the way the cartridge is off set in the mag. It already is a good size grip. I like mine.
 
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