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Old 12-27-2016, 11:36 AM   #1201
Tyneras
 
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Default Re: Gaming Ballistic - GURPS Content Posts

Is there, buried in here somewhere, a way to calculate penetration based purely off projectile velocity and mass? The calculator I've got seems overly complicated for this.
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Old 12-27-2016, 11:39 AM   #1202
DouglasCole
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Originally Posted by Tyneras View Post
Is there, buried in here somewhere, a way to calculate penetration based purely off projectile velocity and mass? The calculator I've got seems overly complicated for this.
mass, velocity, and caliber are needed, though you could probably do well enough by assuming rifles are 6.5mm, pistols are 10mm, and big-ol' machineguns are 15mm or so, and turn that into a constant.
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Old 12-27-2016, 04:43 PM   #1203
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mass, velocity, and caliber are needed, though you could probably do well enough by assuming rifles are 6.5mm, pistols are 10mm, and big-ol' machineguns are 15mm or so, and turn that into a constant.
I have that (messing with muskets, so simple lead balls of various sizes for the moment) I guess I'm just having trouble reverse engineering the Ballistics Model July 30-2013 sheet to convert things into GURPS stats.

This thread is also very intimidating to dig through based on sheer size alone.
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Old 12-27-2016, 06:11 PM   #1204
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Originally Posted by Tyneras View Post
I have that (messing with muskets, so simple lead balls of various sizes for the moment) I guess I'm just having trouble reverse engineering the Ballistics Model July 30-2013 sheet to convert things into GURPS stats.

This thread is also very intimidating to dig through based on sheer size alone.
Somewhere I did a super-simple "just enter the three things and have done with it" calculation. I can reproduce it quickly.

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Old 12-27-2016, 06:46 PM   #1205
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Somewhere I did a super-simple "just enter the three things and have done with it" calculation. I can reproduce it quickly.

dhc
If you want, I still have the spreadsheet that I used from Doug's original stuff. I used it for Old West guns, where I had the original muzzle velocity for the rounds, the bullet mass, and calibers. If you filled in the information, it would give you the rest of the information in GURPS damages.

The damage values are strictly for the cartridges themselves, not for the weapon they're used in. Longer barrels probably improve the damage done (unless too long perhaps?) and shorter barrels probably delivered less damage (ie the muzzle velocity probably shouldn't be THAT high). But it is in the ball park of what you're looking for I'm guessing.

If you want the spreadsheet that I have (it will contain all of the black powder bullet damages that I could get my hands on for all of the 1860's on up to about 1900's black powder cartridges) - email me directly, and I'll send it to you.
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Old 12-27-2016, 06:54 PM   #1206
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If you want, I still have the spreadsheet that I used from Doug's original stuff. I used it for Old West guns, where I had the original muzzle velocity for the rounds, the bullet mass, and calibers. If you filled in the information, it would give you the rest of the information in GURPS damages.


If you want the spreadsheet that I have (it will contain all of the black powder bullet damages that I could get my hands on for all of the 1860's on up to about 1900's black powder cartridges) - email me directly, and I'll send it to you.
Yeah, go ahead and send that around as needed.
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Old 12-27-2016, 06:56 PM   #1207
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The damage values are strictly for the cartridges themselves, not for the weapon they're used in. Longer barrels probably improve the damage done (unless too long perhaps?) and shorter barrels probably delivered less damage (ie the muzzle velocity probably shouldn't be THAT high). But it is in the ball park of what you're looking for I'm guessing.
Better to say that the damage values assume that the energy developed is from a particular weapon/cartridge combination, from which you probably got your velocity numbers. If you chop down the barrel or fire from a longer one, there's no real good way to model your way to better KE numbers if you're just working with mass, velocity, and caliber.
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Old 12-27-2016, 08:29 PM   #1208
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Better to say that the damage values assume that the energy developed is from a particular weapon/cartridge combination, from which you probably got your velocity numbers. If you chop down the barrel or fire from a longer one, there's no real good way to model your way to better KE numbers if you're just working with mass, velocity, and caliber.
Since Cartridges of the World doesn't mention what was used to derive the velocity values - I can only guess. The other book I used that was about the guns of the west, apparently used the same material in the Cartridges of the World (or at least the same authors).

At one point in time, I started compiling a database of guns listed in THE GREENHILL MILITARY SMALL ARMS DATA BOOK by Ian Hogg (guns listed up to about 2000 AD), and then thought "who would ever use this?". Then I thought "Would I even want to take the time to do it if I only want specific guns?"

Ultimately? If people use your spreadsheet and the formulas - they can create their own stats for any gun they want to. The only thing I couldn't figure out was the half damage range and max damage range values. But if they're listed in other GURPS books for a given cartridge, I figured I could just use THOSE values.

The relevant formulas I used were:

Foot/Pounds
=H2*I2^2/450395

Where the data in H2 was weight in grains and I2 was Velocity in feet per second.

Muzzle energy was equal to the value above as "A2" to get the value of Muzzle Energy in Joules.

=1.35581794833189*A2

Damage points was:

=ROUND(SQRT((B2^1.04)/((PI()*((E2/39.37)/2)^2)^0.314))/13.3926,1)

Where B2 is Muzzle energy in Joules, E2 was Bullet Diameter.

From THAT, we finally arrived at the dice value in GURPS terminology by:

=CONCATENATE(INT(C2/3.5),"d+",FLOOR(3.5*(C2/3.5-INT(C2/3.5)),1))

C2 is the Damage points from above.

And that's the bulk of the information I used from your spreadsheet formulas to get what I had. It seemed to work in a large part, to where the values I got from various sources matched what Hans put out in the Adventure Guns supplement. There were a couple of times where it wasn't exactly the same, but that would have been akin to using 2d6+2 versus 3d6-1 kind of thing. Both would have given an average damage value of 9 ish...

Do you want me to send you the file direct in case someone else wants it and I don't notice it?
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Old 12-27-2016, 08:31 PM   #1209
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Since Cartridges of the World doesn't mention what was used to derive the velocity values - I can only guess.
Typically they use 'fire the gun and measure'. Accurate models of gun performance are really too complex for RPG-suitable math.
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Old 12-27-2016, 09:00 PM   #1210
hal
 
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This is a listing of the rounds I put in the database. If I could find a year associated with the round's introduction, I added it.

.22 Short
.22 Long
.22 Long Rifle
.22 Extra Long
.22 Win Rimfire (WRF)
.25 Short
.30 Long
.30 Short
.32 Extra Short
.32 Short
.32 Long
.32 Extra Long
.38 Short
.38 Long
.38 Extra Long
.38 Smith & Wesson
.41 Short
.41 Long
.41 Long Colt
.44 Short
.44 Bull Dog (Webley)
.44 Colt
.44 Smith & Wesson American
.44 Smith & Wesson Russian
.44 Long
.44 Extra Long
.44 Henry Flat
.45 Colt
.45 Smith & Wesson
.45 Smith & Wesson
.45-90 Sharpes
.50 Rem Navy
.50 Remington Army
.56-46 Spencer
.56-50 Spencer
.56-52 Spencer
.56-56 Spencer


.22 BB Cap
.22 CB Cap
.22 Extra Long Rimfire
.22 Long Rimfire
.22 Long Rifle Rimfire
.22 Short Rimfire
.22 Winchester Rimfire (.22 WRF, .22 Remington Special)
.22 Winchester (.22 WCF)
.22 Maynard
.22-15 Stevens
.236 Lee (6mm Lee Navy)
.25 Short Rimfire
.25 Stevens Rimfire
.25-20 single shot Remington
.25-20 Winchester (.25-20 WCF)
.25-21 Stevens
.25-25 Stevens
.25-36 Marlin
.30 Long Rimfire
.30 Short Rimfire
.30-30 Wesson
.30-30 Winchester
.30-40 Krag
.32 Ballard Extra Long
.32 Extra Short Rimfire
.32 Extra Long Rimfire
.32 Long Rifle Centerfire
.32 Long Rifle Rimfire
.32 Short Rimfire
.32-20 Winchester
.32-30 Remington
.32-35 Stevens & Maynard
.32-40 Ballard (.32-40 WCF, .32-40 Winchester)
.32-40 Ballard
.32-40 Remington(.32-40-150)
.32-40 Winchester (.32 WCF, see .32-40 Ballard)
.35-30 Maynard
.35-40 Maynard
.38 Ballard Extra Long
.38 Extra Long Rimfire
.38 Long Centerfire
.38 Long Rimfire
.38 Short Rimfire
.38-35 Stevens
.38-40 Remington(-Hepburn)
.38-40 Winchester (.38-40 WCF)
.38-45 Ballard
.38-45 Stevens
.38-50 Maynard
.38-50 Ballard
.38-50 Remington-Hepburn
.38-55 Ballard
.38-55 Winchester (See .38-55 Ballard)
.38-56 Winchester
.38-70 Winchester
.38-72 Winchester
.38-90 Winchester Express
.40-40 Maynard
.40-50 Sharps (.40-1 11/16ths)
.40-50 Sharps (.40-1 7/8ths)
.40-60 Marlin
.40-60 Maynard
.40-60 Winchester (.40-60-210, .40-60 WCF)
.40-63 Ballard
.40-65 Ballard (.40-65 Ballard Everlasting)
.40-65 Winchester (.40-65-260)
.40-70 Ballard (See .40-63 Ballard)
.40-70 Maynard
.40-70 Peabody "What Cheer"
.40-70 Remington (see .40-70 Sharps necked)
.40-70 Sharps (.40-2 1/4, .40-70 Remington)
.40-70 Sharps (.40- 2 1/2)
.40-70 Winchester (.40-70-330)
.40-72 Winchester (.40-72-330, .40-72 WCF)
.40-75 Ballard
.40-82 Winchester (.40-82-260, .40-82 WCF)
.40-85 Ballard
.40-90 Ballard
.40-90 Bullard (not a typo)
.40-90 Peabody "What Cheer"
.40-90 Sharps (.40-2 5/8ths)
.40-90 Sharps (.40- 3 1/4)
.41 Long Rimfire
.41 Short Rimfire
.44 Ballard Extra Long (.44 Extra Long Centerfire)
.44 Evans (.44 Evans Short)
.44 Evans New Model (.44 Evans Long, .44-40 Straight, .44-40-300)
.44 Extra Long Rimfire
.44 Henry Rimfire
.44 Long Centerfire
.44 Long Rimfire
.44 Short Rimfire
.44 Wesson Extra Long - See .44 Ballard Extra Long
.44-40 Winchester (.44-40 WCF)
.44-60 Peabody Creedmore - See .44-60 Sharps
.44-60 Sharps (.44-60 Sharps necked, .44-60-1 7/8ths)
.44-60 Winchester - See .44-60 Sharps
.44-70 Maynard
.44-75 Ballard Everlasting
.44-77 Sharps (.44-77 Remington)
.44-85 Wesson
.44-90 Remington
.44-90 Remington Special
.44-90 Sharps
.44-95 Peabody "What Cheer"
.44-100 Ballard
.44-100 Remington Creedmore
.44-100 Wesson
.45 Colt Revolver (.45 long Colt)
.45-50 Peabody
.45-60 Winchester
.45-70 Government
.45-75 Sharps
.45-75 Winchester
.45-82 and .45-85 Winchester - see .45-90 Winchester
.45-90 Winchester
.45-100 Ballard
.45-100 Sharps
.45-120 Sharps
.45-125 Winchester
.50-50 Maynard
.50 Government Carbine
.50-70 Government Musket
.50 Remington Rimfire
.50-90 Sharps (.50-100 or .50-110 depending on powder/bullet weights)
.50-95 Winchester
.50-115 Bullard
.50-140 Sharps
.50-140 Winchester Express - See .50-140 Sharps
.55-100 Maynard
.56-46 Spencer Rimfire
.56-50 Spencer Rimfire
.56-52 Spencer Rimfire
.56-56 Spencer Rimfire
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