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Old April 9, 2019, 03:20 PM   #126
Lohman446
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Quote:
Originally Posted by 74A95
Buffalo Bore's 357 Magnum 125 GDHP clocked at 1328 fps producing 489 ft. lbs. ME.
https://www.buffalobore.com/index.ph...t_detail&p=122

Just for comparison and curiosities sake I ran over to Buffalo Bore's sight, picked out a +P round close in weight (124), and looked at what they were showing. Out of a 4" auto barrel they are showing 1296 FPS. Since the overall length of a 9MM is 1.169 inches we would still be dealing with close to the equivalent of a 3" revolver barrel and we still have not accounted for any ground lost due to cylinder gap. I would say its pretty safe to say that on the upper end of the loads the 357 has more power than the 9MM. I would also note the .357 is likely to be readily available with different bullet profiles because there was "never" a concern about loading .357 in an auto-loader.

Does energy (power) matter? I haven't shot a 9MM snub-nosed revolver and comparing recoil with an auto-pistol is not really fair (auto-pistols no doubt require and use some recoil to operate). For me .357 in a snub nose revolver has always been HARSH. I'm not sure how close hot +P 9MM would be in recoil. For me the biggest advantage of .357 (or .38) would be in the different bullet profiles that would be likely to be used for different things (for instance if in bear territory and HP round designed to expand is likely not a great thing)

As I no longer have any interest in touching off HOT .357 in a lightweight snub nose revolver the discussion is purely academic other than wondering if 9MM is just as aggressive in regards to recoil.

Last edited by Lohman446; April 9, 2019 at 03:35 PM.
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Old April 9, 2019, 05:44 PM   #127
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9mm recoil in my 12.5 oz snubs is brisker than .38+P and milder than .357Mag.
It really isn't bad at all.

Keep in mind that semi barrel length is measured breech to snout (3.15" in my Micro 9)
Breech to snout length in my 1-7/8" 637-2 is 3.5".
The revolver loses a bit of velocity due to the cylinder gap.
The semi loses a bit of velocity due to operating the slide.
Velocities out of the 9mm 637-2 are about 45-50 fps greater than the Micro 9.
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Old April 9, 2019, 05:51 PM   #128
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Originally Posted by Lohman446 View Post

As I no longer have any interest in touching off HOT .357 in a lightweight snub nose revolver the discussion is purely academic other than wondering if 9MM is just as aggressive in regards to recoil.
Recoil estimates in gun of same weight (2 lb for purposes of calculations);

9mm Luger 124 at 1150 fps. 6 gr powder = 3.71 ft lbs recoil

9 Major* 125 at 1394 fps. 8.5 gr powder = 5.85 ft lbs recoil

357 Magnum 125 at 1450 fps. 20 gr powder = 8.01 ft lbs recoil


* 9 Major is a really fast 9mm luger loaded for IPSC/USPSA competition. Velocity and powder charge based on my chronographed speed from a 5" barrel and 3N38 powder.

The generic 9mm and 357 mag are based on nominal speeds for those calibers from a 4" barrel.
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Old April 9, 2019, 05:54 PM   #129
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The semi loses a bit of velocity due to operating the slide.
Never heard this before. Can you please explain? Thanks.

I do understand that the slide starts to move before the bullet exits.
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Old April 9, 2019, 06:53 PM   #130
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"Never heard this before. Can you please explain? Thanks"
It takes power to operate the slide. That power isn't going into accelerating the bullet.
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Old April 9, 2019, 07:11 PM   #131
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It takes power to operate the slide.
That power isn't going into accelerating the bullet.
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Old April 9, 2019, 07:34 PM   #132
74A95
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It takes power to operate the slide.
That power isn't going into accelerating the bullet.
But it's the power that accelerates the bullet that moves the slide. For every action there is an opposite and equal reaction.

Let's get a physics person in here to work this out.
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Old April 9, 2019, 08:35 PM   #133
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I am a physics person :-)
(though I confess that I spend most of my time on the flapping flight mechanics of articulated, tension battened membrane wings, and not this complicated stuff)
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Old April 9, 2019, 08:42 PM   #134
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So if I hold the slide to prevent it from cycling I would achieve a higher muzzle velocity?
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Old April 9, 2019, 08:46 PM   #135
74A95
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I am a physics person :-)
(though I confess that I spend most of my time on the flapping flight mechanics of articulated, tension battened membrane wings, and not this complicated stuff)
So what does physics say about the power that accelerates the bullet in a slide that moves 1-2mm before the bullet exits and the other case where the slide does not move at all during or after the bullet exits?

If bullet velocity is reduced in the moving slide example, there must be a measurement of how much velocity is lost. Would that be some function of the recoil velocity based on the weight of the slide/gun and resistance of the recoil spring? Surely there is math to figure this out.
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Old April 9, 2019, 10:47 PM   #136
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Wouldn’t the power that operates the slide be part of the recoil. I get there is no such thing as free energy but in the case of a firearm there is a lot of energy generated beyond that used to accelerate the bullet
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Old April 9, 2019, 11:13 PM   #137
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there is a lot of energy generated beyond that used to accelerate the bullet
The burning gunpowder accelerates the bullet.

The burning gunpowder (and the explosion of the primer) is the only energy source when a gun goes bang.

Is there some other source of energy that I'm missing?
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Old April 10, 2019, 12:25 AM   #138
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"Surely there is math to figure this out".

Of course there is - but, it would be far easier and faster to just chrono a few rounds with and without the slide clamped.

I'd rather spend my time looking at the effect of differential aktinofibril displacement on membrane camber distribution :-)

Last edited by JimCunn; April 10, 2019 at 12:32 AM.
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Old April 10, 2019, 12:39 AM   #139
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"I would say its pretty safe to say that on the upper end of the loads the 357 has more power than the 9MM"

Probably so. I assume we are talking about 9x19 at 35,000 psi here, and not 9x23 at 55,000 psi. Only one of my J-frames is chambered for 9x23 - the other two are chambered for 9x19. All three are also chambered for .357 Mag. All three weigh 12.5 oz. BTW, because of the titanium cylinders, I only fire 147gr 9mm in them. And frankly, I don't plan to fire any 9x23 through them ever.

Last edited by JimCunn; April 10, 2019 at 12:56 AM.
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Old April 10, 2019, 12:52 AM   #140
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Originally Posted by JimCunn View Post
"Surely there is math to figure this out".

Of course there is - but, it would be far easier and faster to just chrono a few rounds with and without the slide clamped.

I'd rather spend my time looking at the effect of differential aktinofibril displacement on membrane camber distribution :-)
Okay. Go for it. Be sure to use a large enough sample and a powder with a narrow SD and ES to have confidence that if the velocity spreads overlap, you can statistically distinguish them. Say, 50 rounds under each condition.

Then, of course, one would want to do the physics math to see if the empirical velocity results are consistent with what physics predicts. You know, to confirm the physics theory is consistent with reality.

Let us know what the results are.
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Old April 10, 2019, 12:54 AM   #141
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Probably so. I assume we are talking about 9x19 at 35,000 psi here, and not 9x23 at 55,000 psi. Only one of my J-frames is chambered for 9x23 - the other two are chambered for 9x19. All three are also chambered for .357 Mag. All three weigh 12.5 oz. BTW, because of the titanium cylinders, I only fire 147gr 9mm in them. And frankly, I don't plan to fire any 9x23 through them.
Then what was the point of having it chambered for 9X23?
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Old April 10, 2019, 12:58 AM   #142
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An oops by the gunsmith who did them. It chambers 9x19 just fine, so I don't care.
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Old April 10, 2019, 01:01 AM   #143
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"Let us know what the results are".

My time is better spent on aktinofibrils. Why don't you do it and let us know?
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Old April 10, 2019, 01:14 AM   #144
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This thread is like being on a Merry-go-round!


Agreed. I get a kick out of people using factory loads to prove what a caliber is and is not capable of.

First off, we need to address a big industry myth that has formed a false premise for most of the discussion in this thread: Federal and Remington and other big manufacturers load for pressure, not velocity. Good example is i have chronoed the same 357 “factory load” from Federal on the same day same gun etc. But the identical ammo was from two different lots. There was a 150+ fps difference between the two lots. Pulled the bullets and they were loaded with different powder. Called Federal and was told they load to pressure, not velocity, and switch powders all the time for bulk ammo and even their premium ammo, using whatever powders were available. I’ve spoken with folks at Barnes after Remington acquired them and was told Remington does similarly. I’d be shocked if Winchester was any different. So you see, this whole debate using factory published loads is based on a false premise. The ammo you’re using and testing and arguing about isn’t even consistent from lot to lot.
Now if you go to handloads, where you can control every element of the ammo, you can load the 357 well beyond what 9mm can do, and 9mm does indeed land between 38 special and 357 mag for most powder and bullet combos.
But anyways, you really shouldn’t be debating velocities and powers of different factory loads. Doing so is just based on a false premise.


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Old April 10, 2019, 01:35 AM   #145
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Quote:
It takes power to operate the slide.
That power isn't going into accelerating the bullet.
This is correct. As far as it goes. The power (energy) that operates the slide isn't going into accelerating the bullet. And, it NEVER DOES even when its not operating a slide.

The pressure that operates everything is pushing equally in ALL directions at the same time. It doesn't push the bullet out the muzzle and then run back and work the slide. The amount of force does change as the size of the vessel containing it changes (expansion ratio), and there is also change due to progressive burning of the powder, but one fact of physics that does not change is that all the available pressure at any moment in time is equally distributed across the entire surface area of the closed vessel.

The small movement of the slide AND barrel, locked together, before the bullet exits the bore, can have NO effect on the pressure pushing the bullet. Locked together, there is no change in the size of the space the powder gas fills, other than the increase due to the bullet moving down the bore, an that is the same, whether there is a slide, or not.

And, until the bullet exits the muzzle, it's a closed system. All the pressure is still contained inside. No bleed off, no way for the pressure to change, no where for it to go, until the exit of the bullet vents the system.

Pressure is pushing in all directions. Pressure on the sides, top and bottom seals the brass to the chamber walls. Pressure on each end pushes equally as well, moving the bullet faster (because its much lighter) and further (because its not fastened to anything). That same pressure is pushing on the case head, and because it can't move, on the slide. Nothing is "taken away" from the pressure on the bullet.

But, just for the sake of argument, let's say it did actually "drain" some of the force pushing the bullet. SO WHAT??? Any velocity "stolen" from the bullet by moving the slide before the bullet leaves the barrel will be less than the variation between individual guns and likely individual rounds of ammo.

you may find a calculatable difference, but you won't find a practical difference, so it is, in effect, irrelevant.
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Old April 10, 2019, 02:19 AM   #146
74A95
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Quote:
Originally Posted by JimCunn View Post

My time is better spent on aktinofibrils.
Why don't you tell the readers what aktinofibrils are, since you seem to be proudly boasting about studying them. And are they living or fossil?

Quote:
Originally Posted by JimCunn View Post
Why don't you do it and let us know?
You proposed the idea, you have the burden of proof to demonstrate it.
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Old April 10, 2019, 04:46 AM   #147
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I tried it, it works.

Also, cut a circular hole in the bottom of the pill bottle with a diameter just less than the location of the primers. The purpose being to assist in pushing the moon clip out with a finger (if need be) while still protecting the encapsulated primers from being struck by something in your pocket.



Give the pill bottle base a slight twist as you extract it after you drop the rounds into the cylinder. That assists in releasing the bottle base from the moonclip.

Definitely give you a for ingenuity...

However, just from practice, I prefer the Del Fatti carriers. To me, I prefer the carrier out of the equation by the time I get to inserting the moonclip into the cylinder.







If I’m reloading under stress, that carrier is flying off the reload pretty quick... due to the extended button. After that, I’ll worry about it after everything settles down... if appropriate.
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Old April 10, 2019, 05:46 AM   #148
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"To me, I prefer the carrier out of the equation by the time I get to inserting the moonclip into the cylinder".

A lot to be said for that. Good point. However, they do eat up a lot of storage volume till you dump the carriers.

I liked Post #144. All these various rounds will do the job just fine (I even carry a Micro .380 a good bit of the time).

For me (in no particular order), the main benefits of the 9mm in the snubbie are
Ammo commonality with two of my four semi-automatics
Very quick ejection and reloading
Reduced volume of reserve ammunition (9mm rounds are relatively small)
I don't particularly like semi-automatics - I do like single action revolvers.

Totally off-topic - A public announcement about the EHT is live streaming at 8 am Central time this morning. Possibly the first images of the event horizons of Sagittarius A* and maybe M87. I'm excited (which is why I'm up this early - I'm not a morning person)

Last edited by JimCunn; April 10, 2019 at 06:39 AM.
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Old April 10, 2019, 06:00 AM   #149
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Quote:
The burning gunpowder accelerates the bullet.

The burning gunpowder (and the explosion of the primer) is the only energy source when a gun goes bang.

Is there some other source of energy that I'm missing?
No but there is some implication here that the energy from that explosion is used efficiently only to accelerate the bullet.

There is a lot of energy that is "lost" in the equation to things other than the intended use. Hence recoil. If all the energy was being used solely accelerated the bullet than the premise that any energy used for anything else is lost. But this energy is already lost to recoil.

Thus if I can steal energy that would otherwise go to recoil to operate the slide I would not be stealing any energy that actually accelerated the bullet.
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Old April 10, 2019, 06:46 AM   #150
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I haven't read the Havamal. Is anything in it attributed to Gudrid Thorbjarnardóttir?
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