D&D 5E Why do guns do so much damage?

[Steampunkette]

Which is why bullets don't throw people backwards. Momentum is not at all the same thing as force, nor does it matter at all to the damage of a bullet, except that you might derive velocity from it, which can be a useful number.

We're back to the claim that flintlock pistols had half the velocity of the rifle, I see. I went back, after our last toss on this, and looked up where this entered the thread. The only provenance for this is that you said a friend messaged you and told you this fact. No source, no cite. It doesn't align with the actually sourced and cited data in the thread, which show a velocity of just below 400m/s, empirically tested. And, before the claim of "modern powder" shows up again, the flintlock muskets had about the same velocity you're claiming from whatever source you have, so modern powder cannot both replicate the muskets AND be the cause of supercharged pistols in the same study with the same methodology. I mean, they use half the charge in the pistol (they list all the pertinent data). So, no, half the velocity is a non-starter.

However, if we're looking at that 200 grain musket ball from the flintlock musket (which seems light, given the Brown Bess was over 500 grains), then the kinetic energy is 2,229 kgm^2/s^2 (I'm not sure where you get the above, are you using a different weight than 0.013kg? As I said, this looks very light, but I'm trying to stick to your numbers). To give a reference, the .44 Magnum pistol cited in your article has a kinetic energy of 1147J at the muzzle. The flintlock pistol listed in @Doug McCrae's article is 1071J. Seems we're absolutely in the danger zone with both!

Wrong units for force, and the force of the flintlock musket about is dramatically higher. The actual acceleration value isn't the same as the velocity, because it has to reach that velocity down an approx 1 meter barrel in about 4 milliseconds. Your previous calculations for bullet force are off by about 3 orders of magnitude. Acceleration is around 103,000 m/s^2, not 414. So it's not 0.013kg*414, it's 0.013kg*103,000, or 1,339N of force, in an area about 2/3 of an inch across (actually, this force will be transferred along the path -- it's not an inelastic collision so all the force isn't immediately applied).

Swords are nasty, but your evaluation of bullets is consistently very far off the mark.

I hope I've provided enough clear points, and addressed the previously cited counter-points, sufficiently well to avoid being accused of bad-faith and being blocked, again.

I went off the basis of the 414m/s muzzle velocity from this video using a .8 bore musket with a .69 ball. The same size as the Brown Bess. However it isn't a 13 gram ball. That's for the Pistol. The Musketball is 32 grams. It's listed in the thread.


Which not only includes a healthy discussion of the differences between modern gunpowders but also the cavitation created by that impact. Skip forward to 9:50 and you can see nice visual charts showing the actual measurements of the temporary cavity, the purpose of using the Ballistic Gelatin in this case.

The whole "300m/s" thing comes from Flamestrike posting speeds of Musket Balls ranging from 120m/s up to 370m/s from a Wikipedia article. Y'know. Finding the Average since the musket we'd be talking about would be about 200-300 years older than the Brown Bess.

As to the pistol velocity being lower, it's based on the Wheellock Pistol video by the same person.


Skip ahead to about 18:26 for a discussion of the paper cartridge's muzzle velocity and joules. Which were lower than I got from using the speed of the flintlock pistol in the kinetic energy calculator linked previously in the thread. Same one I used to get the 2793J for the Musket at 414m/s and .032kg weight.

Kinetic Energy Calculator

Calculate any variable in the kinetic energy equation. Kinetic energy is equal to half the mass multiplied by velocity squared: KE = 1/2 * mv^2. Physics calculators online.

www.calculatorsoup.com

Though if you want Newtons you're gonna need this one:

Force Calculator F = ma

Calculate the unknown variable in the equation for force, where force equals mass multiplied by acceleration. Free online physics calculators.

www.calculatorsoup.com

Using this Acceleration Calculator: Acceleration Calculator | Definition | Formula

I input 0m/s, 414m/s, and 0.024 seconds as the time interval (rounding off) for a total of 172,500m/s squared for acceleration. Toss that in the Force Calculator for the 0.032kg weight for a total of 5520N.

Just for the average muzzle velocity of muskets I went ahead and did it again with 300m/s and a time of 0.0033. Wound up with an acceleration of 90909m/s squared and a Force of 2909N.

Just for the sake of completeness, let's knock out the Wheellock while we're at it. With a Muzzle Velocity of 271m/s and a barrel length of 0.4 meters (16 inches). Because it's less than a meter I divided 1 second by the speed, then multiplied the result by 0.4 to get a time interval of 0.0014 seconds. Toss that in the acceleration calculator and we get 193,571m/s squared. Pop that into the Force Calculator with a .013kg ball and... 2516N

Somehow that feels wrong but I'm not sure where I messed up, or if I messed up. Help?

Now for the Sword. A bit wilder. But here's the source: http://swordstem.com/2018/08/22/how-fast-do-swords-move-try-1/

They provide a chart image I can't embed on these forums that shows the sword's strike time taking about 0.145 seconds. So 0 to 21m/s in 0.145 seconds into the acceleration gives us: 144m/s squared.

And then toss that into the Newtons Calculator with a 1.5kg longsword and: 217N

Yup! That is significantly tiny by comparison to the Force of the musketball. Thanks for correcting me on this! Weird that the Momentum would swing the other way.

However... The video at the start of this, with the 414m/s muzzle velocity .69 caliber bullet shows the temporary cavity as being 3 inches wide at it's largest point. Which Emergency Room Doctors say isn't a significant wounding factor. That it takes a 4 inch to 10 inch temporary cavity to provide a significant wounding factor. Something that a .44 Magnum or a modern Rifle with a tumbling and/or yawing bullet can provide.

Except in cases where an organ is struck by that temporary cavity that is particularly sensitive like the brain or liver, obviously. 3 inches is more than enough to push the no more birthday button, there, unless you're very lucky.

 

[wellis]

What kind of guns do you think elves might wield, considering the general fantasy takes on their sense of aesthetics and high quality workmanship?

Something functional, beautiful, yet relatively high powered or potentially quick loading?

 

[Steampunkette]

What kind of guns do you think elves might wield, considering the general fantasy takes on their sense of aesthetics and high quality workmanship?

Something functional, beautiful, yet relatively high powered or potentially quick loading?

Elven Rifles... Hmm...

I don't think they'd -use- rifles as a culture. Too easy. Inelegant. When you've got 700+ years to master something a point and pull weapon becomes trivial. They're also "Newfangled" even when they've been around for 200 years. Plus the pain in the ears would be rough!

That said... I could see a lot of elves with fancy looking heavily artsy firearm -display- pieces where they carve the stock and inlay the barrel in an attempt to get as much artistry into it all as possible.

And I could see individual elves who are Trickshooters, because that takes a lot of skill and timing. But they'd likely be the iconoclastic members of their race? The ones who spent the majority of their long lives enamored of the shorter-lived races of the world. Perhaps traveling with carnivals or wandering the lands learning every quick draw technique they can to perfect their particular art.

 

[QuentinGeorge]

What kind of guns do you think elves might wield, considering the general fantasy takes on their sense of aesthetics and high quality workmanship?

Something functional, beautiful, yet relatively high powered or potentially quick loading?

Elves rock derringers. You know it makes sense.

 

[Neonchameleon]

What kind of guns do you think elves might wield, considering the general fantasy takes on their sense of aesthetics and high quality workmanship?

Something functional, beautiful, yet relatively high powered or potentially quick loading?

Assuming we're going with the muzzle loading era? They get individually handmade breechloaders closed by a hand-crafted screw thread in the style of the Ferguson Rifle (or more accurately in the style kings used to get a century earlier). Very low power by musket standards and exceptionally finnicky because it's easy to foul the hand-crafted screw thread with e.g. powder (which is part of the reason elves go for lower power smokeless powder). But on the plus side it's got the fire rate of a breechloader.

 

[Steampunkette]

Gonna go ahead and do a .44 Magnum 340 grain bullet for comparison, using a 10 inch barrel for a .25m length. Following the same formula as before and using the Magnum's 434m/s muzzle velocity for the Buffalo Bore bullet we get 754,783m/s squared.

Toss that into the Force Calculator with the bullet's 22grams and... 16,605N. More than 3 times the Newtons of the .69 caliber 32 gram musket ball. Plus the bullet Yawing or Tumbling in the wound...

And that one WILL put the 4 inch diameter temporary cavity in you that the Emergency Room Staff will consider to be a Significant Wound Factor.

Will the comparative Newtons between a modern HANDGUN and a peak-power LONG ARM finally show you (general you, not any individual) how huge a difference there is between modern firearms and firearms 400 years ago?

 

[Wyldekarde]

This might help for comparisons. There's a lot of data for firearms but not enough for medieval weapons so this might add some insight regardless of the position on this topic.

Impact Analysis of Medieval Weaponry

Impact Analysis of Medieval Weaponry

www.academia.edu

 

[Steampunkette]

This might help for comparisons. There's a lot of data for firearms but not enough for medieval weapons so this might add some insight regardless of the position on this topic.

Impact Analysis of Medieval Weaponry

Impact Analysis of Medieval Weaponry

www.academia.edu

That is super interesting... but it registers the impact force as 12,000+ Newtons for the Claymore and 7,000+ for the Katana.

Is it because in my above calculations for a longsword I used the overall speed without accounting for the difference in acceleration between the grip and the striking surface as separate locations in a radial arc? 'Cause Katana are similar in size and weight as a European longsword and that's a MASSIVE increase over the 217N I got from the calculator. Would also help to account for the claymore's even larger increase since the striking point is further from the hilt than the striking surface of the Katana...

Also... here's a video of a .44 magnum firing a round that hits a Ballistics Gelatin target!


Look at the temporary cavity stretch nearly the full size of the block (6 inches square on it's face)! At it's widest point that's easily 4-5 inches. And then the cavitating bubble forms as the pressures compress the gasses yanked into the vacuum left behind the bullet and cause an explosion inside the gel block.

Something you sure as heck don't see in the Flintlock Musket video with only 1/3rd the Newtons!

 

[Stalker0]

So I did a little research of my own:

Warcraft III - Humans -> Units -> Footman

Warcraft III - Humans -> Units -> Rifleman

As you can see a typical "Footman" wielding a longsword does an average of 9.26 damage per second, where as the equivalent "Rifleman" of that era do a full 14 damage per second. Those are blunderbuss rifles for those interested, and using your standard gunpowder. Of course no mithril swords or magic gunpowder was used as that might skew the results.

I believe I have tied off this argument with a nice little bow.

 

[Ovinomancer]

I went off the basis of the 414m/s muzzle velocity from this video using a .8 bore musket with a .69 ball. The same size as the Brown Bess. However it isn't a 13 gram ball. That's for the Pistol. The Musketball is 32 grams. It's listed in the thread.


Which not only includes a healthy discussion of the differences between modern gunpowders but also the cavitation created by that impact. Skip forward to 9:50 and you can see nice visual charts showing the actual measurements of the temporary cavity, the purpose of using the Ballistic Gelatin in this case.

The whole "300m/s" thing comes from Flamestrike posting speeds of Musket Balls ranging from 120m/s up to 370m/s from a Wikipedia article. Y'know. Finding the Average since the musket we'd be talking about would be about 200-300 years older than the Brown Bess.

As to the pistol velocity being lower, it's based on the Wheellock Pistol video by the same person.


Skip ahead to about 18:26 for a discussion of the paper cartridge's muzzle velocity and joules. Which were lower than I got from using the speed of the flintlock pistol in the kinetic energy calculator linked previously in the thread. Same one I used to get the 2793J for the Musket at 414m/s and .032kg weight.

Kinetic Energy Calculator

Calculate any variable in the kinetic energy equation. Kinetic energy is equal to half the mass multiplied by velocity squared: KE = 1/2 * mv^2. Physics calculators online.

www.calculatorsoup.com

Though if you want Newtons you're gonna need this one:

Force Calculator F = ma

Calculate the unknown variable in the equation for force, where force equals mass multiplied by acceleration. Free online physics calculators.

www.calculatorsoup.com

Using this Acceleration Calculator: Acceleration Calculator | Definition | Formula

I input 0m/s, 414m/s, and 0.024 seconds as the time interval (rounding off) for a total of 172,500m/s squared for acceleration. Toss that in the Force Calculator for the 0.032kg weight for a total of 5520N.

Just for the average muzzle velocity of muskets I went ahead and did it again with 300m/s and a time of 0.0033. Wound up with an acceleration of 90909m/s squared and a Force of 2909N.

Just for the sake of completeness, let's knock out the Wheellock while we're at it. With a Muzzle Velocity of 271m/s and a barrel length of 0.4 meters (16 inches). Because it's less than a meter I divided 1 second by the speed, then multiplied the result by 0.4 to get a time interval of 0.0014 seconds. Toss that in the acceleration calculator and we get 193,571m/s squared. Pop that into the Force Calculator with a .013kg ball and... 2516N

This is very messy. To start, the units don't work. You took seconds divided by meters per second, which ends up as seconds squared per meter, and then multiplied by meters for seconds squared.

What you wanted to do was assume constant acceleration (reasonable here) and look at d=1/2at^2, and v=at, so subbing you get d =1/2vt. Time will be t=2d/v, or 2(.4m)/271m/s (for arguments sake, I'm taking this number, although there's strong evidence to the different). This is 3ms, or 0.003seconds. Going back through, that's an acceleration of 90.3km/s or so.

Plugging that into F=ma and you get 0.013kg(90,300m/s^2)= 1174N.

Thing is that's a tiny bullet. 13 grams is a bullet almost a 1/3 the size of the musket. This isn't born out by visuals, or the record, where pistols fired shot about the same size as the muskets, until the advent of the revolver, at least.

Somehow that feels wrong but I'm not sure where I messed up, or if I messed up. Help?

Now for the Sword. A bit wilder. But here's the source: http://swordstem.com/2018/08/22/how-fast-do-swords-move-try-1/

They provide a chart image I can't embed on these forums that shows the sword's strike time taking about 0.145 seconds. So 0 to 21m/s in 0.145 seconds into the acceleration gives us: 144m/s squared.

And then toss that into the Newtons Calculator with a 1.5kg longsword and: 217N

Yup! That is significantly tiny by comparison to the Force of the musketball. Thanks for correcting me on this! Weird that the Momentum would swing the other way.

Not really. Look at the formulas and see what mass and velocity and acceleration do. Mass is the same in both -- double it and you double both. Velocity and acceleration are very different beasts, though, and you've seen in the calculations that to get a velocity of X, the acceleration for a bullet to get there is orders of magnitude higher. So, on that alone, it makes a lot of sense that a bullet's momentum is low but it's force is high -- the difference between v and a is large. For a sword, though, v and a are closer, so the momentum and force are closer -- same order of magnitude at least.

However... The video at the start of this, with the 414m/s muzzle velocity .69 caliber bullet shows the temporary cavity as being 3 inches wide at it's largest point. Which Emergency Room Doctors say isn't a significant wounding factor. That it takes a 4 inch to 10 inch temporary cavity to provide a significant wounding factor. Something that a .44 Magnum or a modern Rifle with a tumbling and/or yawing bullet can provide.

Except in cases where an organ is struck by that temporary cavity that is particularly sensitive like the brain or liver, obviously. 3 inches is more than enough to push the no more birthday button, there, unless you're very lucky.

I'm not sure you can read those graphs that way -- it doesn't label either, and their gel does an odd thing in how it sustains visible damage much wider than the permanent wound track. Normal ballistic gel doesn't do this because it's highly elastic and so you can only see the scope of the temporary expansion in slow mo. So, I'm not exactly convinced their graph (which closely matches the visible damage done) is actually the scope of the temporary cavity rather than where a poorly mixed ballistic gel sustained damage due to tearing. It's not at all clear from that video (and the second one you link has properly mixed gel and doesn't sustain damage outside the permanent wound track).

I cited the actual ballistic data for a .44 magnum, which your cited article said was a high cavity weapon, and it is in the ballpark of the numbers being calculated for flintlock pistols here. The number I calculated, and which was the same using your cited calculators (because I was using the same formulas), are nearly identical for a musket. This makes a musket a very deadly weapon, doing massively more damage than you expected. The pistol, even accounting for the lower velocity you want, is still very dangerous, with numbers close. The only cite in thread that showed pistol data lists a flintlock at very near that same number for the .44 (and this makes sense once you account for an actual larger caliber rather than the odd very low bullet size you calculated). Flintlocks were very dangerous weapons, and not far behind or on par with some modern weapons in power (if not accuracy or reliability). It's only when you get to the high-power stuff that modern firearms (and we're talking rifles here) really get away from them. The size of the shot and the power of the weapon meant that it was very, very damaging.

And, again, this has nothing at all to do with how you represent firearms in game.