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Deadman

Guns and Ammo

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I have been doing some thinking on Guns and Ammunition lately.  I've always liked the Dark Champions genre as I am something of a realism nut.  I did some deep digging into the Hero System Firearms damage tables (in Dark Champions 5e incidentally).  What I found was a more or less true correlation of Muzzle Energy to Damage Classes.  Each Damage Class is supposed to represent double the Energy (in Joules) of the previous.  This is fairly well represented in the table (with the occasional stray).  I was thinking of a way to further break down Damage to add some flavor to Firearms Damage Classes.  First I guess I should share my findings.

 

Firearms Damage
DC Joules Example Kdamage
1 50 BB Gun 1 pip
2 100 .22 Long Rifle 1/2d6
3 200 .380 ACP 1d6
4 400 9mm, .45 ACP 1d6+1
5 800 .357 Magnum 1 1/2d6
6 1600 .44 Magnum 2d6
7 3200 7.62 2d6+1
8 6400 .458 Win Magnum 2 1/2d6
9 12500 .50 BMG

3d6

 

Now honestly the chart above does a passable job for the most part.  However, it is my opinion that the DCs could be broken down even more to differentiate damage.  According to the chart a 9mm and a .45 ACP round would do the same damage (though I guess you could make an argument for the .45 getting a +1 Stun Multiple and the 9mm not).  What I am proposing is really getting into the minutia of the issue but it will help define things a bit better IMHO.

 

The standard breakdown for Killing Damage is well known among this community 5 Points for 1 Pip, 10 Points for 1/2d6, 15 Points for 1d6.  Easy peasy right?  Well here is what I am proposing.

 
Killing Damage Breakout
Points Kdamage Range
5 1 1
6 1 1
7 1 1
8 1d2 1-2
9 1d2 1-2
10 1d3 1-3
11 1d3 1-3
12 1d3 1-3
13 1d4 1-4
14 1d6-1 0-5
15 1d6 1-6
     
       
       

How this works should be pretty evident.  If you wanted to buy Double Tap 230gr .45 ACP ammunition (which has 639 J of Energy) you could call that a 23 Point RKA meaning a 1d6+d2 attack (it isn't actually adding 2 points to the damage but 1-2, it's just easier to annotate that way).  You would then apply all of your Limitations and Advantages.  In that vein, Remington 240gr Steel Jacketed Hollow Points in .44 Magnum (1,005 J of Energy) would be a 1d6+d4  (28 Points) due to the lower Energy of that specific ammunition. 

 

Now, before you say it...I know that this isn't really necessary.  My question is does it make sense and does it do what I am setting out to do (giving further distinction to Killing Damage)?

 

Next up I will tackle the Handgun/Rifle penetration argument.

 

T

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Does it makes sense?  Yes
Does it do what you are setting out to do (giving further distinction to Killing Damage)? Yes

 

And now the question you didn't ask that should probably also be asked and answered:
Does it do what you are setting out to do (giving further distinction to Killing Damage) with enough material/meaningful distinction to warrant bothering?  No

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What you have proposed is logical and even-handed. I would ask, however, why you are equating watt-seconds and grams. You're listing payload size as examples for energy. That relationship usually involves Einstein's equation.

In other words, accelerating a BB to relativistic speeds would completely blow your carefully plotted examples.

 

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1 hour ago, Surrealone said:

Does it makes sense?  Yes
Does it do what you are setting out to do (giving further distinction to Killing Damage)? Yes

 

And now the question you didn't ask that should probably also be asked and answered:
Does it do what you are setting out to do (giving further distinction to Killing Damage) with enough material/meaningful distinction to warrant bothering?  No

 

I think that question was addressed with the statement "I know that this isn't really necessary".  Surrealone, you of anyone should know that I tweak things just because that is what I do.  Makes me feel better to have some pseudo-scientific way of explaining it.

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Now on to the next point.  How to address the relative lack of penetration of Handgun Rounds when compared with Rifle Rounds.  My first thought was to adjust Armor Piercing and add it to Rifle Rounds.  While I will probably do this anyway since I don't think that Armor Piercing adequately represents what it does.  Meaning that I think that AP should be based on the attack rather than the Target's Defense.  But I digress, on to the subject at hand.

 

There are currently six levels of Body Armor (I, IIA, II, IIIA, III and IV) though technically Level I is no longer part of the standard.  The first 4 levels are available in Soft Body Armor as follows.

 

Level DEF Protects Against
I 4 .22lr, .32, .38
IIA 7 .45ACP,.40S&W, lv9mm
II 8 .357Mag, 10mm, hv9mm
IIIA 9 .357SIG, .44Mag

 

Given the damage that I posted previously the listed amounts will shut down all but the highest rolls and it is fairly easy to assume that the BODY damage that gets through is due to tissue trauma and internal organ damage.  The GM should adjudicate that the round doesn't actually penetrate.

 

The real problem becomes what to do about Rifle rounds which are much more effective against Soft Body Armor.  More so than the little BODY damage that would get through would indicate.  For this reason I think that as part of the Real Armor Limitation it should reflect that Soft Body Armor only has half of its stated value against High Velocity Rifle Rounds.  This could also be represented by an additional Limitation but my feeling is that it is unwarranted.  If the Rifle Round has Armor Piercing it would go against the modified Defense of the Armor.  Of course doing things this way would also mean that Hard Body Armor would need to be bought to a level that could stop the Rifle Rounds outright.  As I mentioned in another thread Hard Body Armor should be bought using Barrier rules which means that if none of the BODY gets through then no STUN is taken.  We'll go into that on my next post...

 

T

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4 hours ago, clnicholsusa said:

What you have proposed is logical and even-handed. I would ask, however, why you are equating watt-seconds and grams. You're listing payload size as examples for energy. That relationship usually involves Einstein's equation.

In other words, accelerating a BB to relativistic speeds would completely blow your carefully plotted examples.

 

Where are you getting the idea that anyone is equating Joules (watt-seconds) with grams? The chart lists the muzzle energies (KE = 0.5mv^2) which are definitely measured in Joules, and gives the Damage Classes associated with that value in the Hero System. The chart also lists, for examples, the kinds of weapons that have muzzle energies near the figure in question. Note that the first entry says "BB gun", NOT "0.34 gram steel sphere". Yes, some kind of sci-fi system could accelerate a standard BB to 0.1c, but that is not what a reasonable person would assume that "BB Gun" means. Furthermore, it would NOT "blow [the] carefully plotted examples"; it would just be another example further down the chart, like this:

DC            Joules                 Example                                        Kdamage

32             1.575e11            4.5mm Hyperkinetic Rifle           10  1/2 d6

 

Edited because I forgot to convert from grams to kilograms, like a complete noob.

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Just a quick FYI for all who didn't already know.  A bullet's mass is measured in Grains which is what the "gr" stands for in the example above.  Each grain equals about .065 Grams. 

 

As Zeropoint pointed out the Energy is equal to the Mass multiplied by the Velocity squared (for Joules the Mass must be in kilograms while the velocity is in meters per second) times 1/2.  This means that the Velocity of an object has a larger factor on its energy.  A baseball (.145kg) moving at 50mph (22.352 m/s) and hitting an object would have approximately 36 Joules of energy (~1d6).  If that baseball were moving at 1000mph (447.04 m/s) it would have approximately 14,500 Joules of energy (6d6).  Using these calculations we can easily determine that a 100mph fastball from a pitcher would have about 145 Joules and do about 2 1/2d6 of normal damage so you can see that doubling the Velocity essentially quadrupled its energy.  On the other hand if we doubled the mass of the baseball (.29kg) and kept it moving at 50mph it would have about 72 Joules of energy (~1 1/2d6).  This shows that the mass, when doubled, only doubles the energy.

 

T

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12 hours ago, Deadman said:

Now on to the next point.  How to address the relative lack of penetration of Handgun Rounds when compared with Rifle Rounds.  My first thought was to adjust Armor Piercing and add it to Rifle Rounds.  While I will probably do this anyway since I don't think that Armor Piercing adequately represents what it does.  Meaning that I think that AP should be based on the attack rather than the Target's Defense.  But I digress, on to the subject at hand.

 

There are currently six levels of Body Armor (I, IIA, II, IIIA, III and IV) though technically Level I is no longer part of the standard.  The first 4 levels are available in Soft Body Armor as follows.

 

Level DEF Protects Against
I 4 .22lr, .32, .38
IIA 7 .45ACP,.40S&W, lv9mm
II 8 .357Mag, 10mm, hv9mm
IIIA 9 .357SIG, .44Mag

 

Given the damage that I posted previously the listed amounts will shut down all but the highest rolls and it is fairly easy to assume that the BODY damage that gets through is due to tissue trauma and internal organ damage.  The GM should adjudicate that the round doesn't actually penetrate.

 

The real problem becomes what to do about Rifle rounds which are much more effective against Soft Body Armor.  More so than the little BODY damage that would get through would indicate.  For this reason I think that as part of the Real Armor Limitation it should reflect that Soft Body Armor only has half of its stated value against High Velocity Rifle Rounds.  This could also be represented by an additional Limitation but my feeling is that it is unwarranted.  If the Rifle Round has Armor Piercing it would go against the modified Defense of the Armor.  Of course doing things this way would also mean that Hard Body Armor would need to be bought to a level that could stop the Rifle Rounds outright.  As I mentioned in another thread Hard Body Armor should be bought using Barrier rules which means that if none of the BODY gets through then no STUN is taken.  We'll go into that on my next post...

 

T

 

I don't enjoy math and all the calculations and Joules and such, so I stay away from all that.

 

But on AP, I don't even know what the current RAW is, as I've always had the house rule that AP means "subtract Body rolled from non-hardened defense before applying"


Pretty simple. To make it a bit more crunchier (and I think you were on the thread I had about this), to address the "rifles penetrate better than pistols" piece, I simply made all long guns "Light AP" by default, meaning "subtract 1/2 Body rolled from non-hardened defense before applying"

 

In playtest, this worked really well. Guns vs. Level IIa body armor, plates adding +3 and making the whole amount "hardened" (how I interpret it anyway). Pistol shots often absorbed with a little stun getting through... no stun is transmitted if hardened armor in not penetrated. Light AP on .300 AAC Blackout vs. Level IIa meant an average roll of 8 body, -4 to 7 rPD, take 5 body... felt really good. Bullet penetrated, but not immediately lethal, where pistol rounds were stopped. High roll on 2d6+1 would mean all or nearly all of the armor was negated, and you'd get that occasional lethal blow through... but if round hit plate coverage, it was generally stopped cold, barring an exceptionally high roll.

 

Then you can get into the rounds being actually AP... subtracting FULL body rolled vs. armor, and that gets really lethal, very quickly, and plates are really important, but that also seems to word. (I generally follow the rule of "damage of standard round turned AP is now -1 DC... so .300 AAC would be 2d6AP, instead of 2d6+1 Light AP)

 

Somewhat crunchier, and plays very well, but not as specifically built to reflect actual ammunition tested velocities and such.

 

18 hours ago, Deadman said:

Killing Damage Breakout

Points Kdamage Range

5 1 1

6 1 1

7 1 1

8 1d2 1-2

9 1d2 1-2

10 1d3 1-3

11 1d3 1-3

12 1d3 1-3

13 1d4 1-4

14 1d6-1 0-5 

15 1d6 1-6

 

As for your break out... which did not quote well here... I would never implement this level of detail in a game where you had to point buy your attacks. Those games are super games and such realism seems out of place to me... but in a Heroic level, more realistically based game, if someone wanted to go through every firearm in the book, and make charts of damage differences based on ammunition loads... I'd think about using that as reference... even though I doubt my game and players would be arguing about which ammunition types they were able to get.

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11 minutes ago, RDU Neil said:

I don't enjoy math and all the calculations and Joules and such, so I stay away from all that.

 

But on AP, I don't even know what the current RAW is, as I've always had the house rule that AP means "subtract Body rolled from non-hardened defense before applying"


Pretty simple. To make it a bit more crunchier (and I think you were on the thread I had about this), to address the "rifles penetrate better than pistols" piece, I simply made all long guns "Light AP" by default, meaning "subtract 1/2 Body rolled from non-hardened defense before applying"

 

In playtest, this worked really well. Guns vs. Level IIa body armor, plates adding +3 and making the whole amount "hardened" (how I interpret it anyway). Pistol shots often absorbed with a little stun getting through... no stun is transmitted if hardened armor in not penetrated. Light AP on .300 AAC Blackout vs. Level IIa meant an average roll of 8 body, -4 to 7 rPD, take 5 body... felt really good. Bullet penetrated, but not immediately lethal, where pistol rounds were stopped. High roll on 2d6+1 would mean all or nearly all of the armor was negated, and you'd get that occasional lethal blow through... but if round hit plate coverage, it was generally stopped cold, barring an exceptionally high roll.

 

Then you can get into the rounds being actually AP... subtracting FULL body rolled vs. armor, and that gets really lethal, very quickly, and plates are really important, but that also seems to word. (I generally follow the rule of "damage of standard round turned AP is now -1 DC... so .300 AAC would be 2d6AP, instead of 2d6+1 Light AP)

 

Somewhat crunchier, and plays very well, but not as specifically built to reflect actual ammunition tested velocities and such.

 

I hear you.  I am not a math wiz either.  However, I am laying the groundwork for what is to come.  See below for details.

 

I remember your thread and that is one of the reasons that I wanted to address this.  I did not include the "light armor piercing" because I am saving that for specific ammunition.  I felt that if it were stated as a function of Soft Body Armor it would  serve as a "House Rule" which could carry throughout the genre.

 

13 minutes ago, RDU Neil said:

As for your break out... which did not quote well here... I would never implement this level of detail in a game where you had to point buy your attacks. Those games are super games and such realism seems out of place to me... but in a Heroic level, more realistically based game, if someone wanted to go through every firearm in the book, and make charts of damage differences based on ammunition loads... I'd think about using that as reference... even though I doubt my game and players would be arguing about which ammunition types they were able to get.

 

What I plan on doing is exactly what you have eluded to.  Creating charts for various ammunition.  I am a bit of a nut for realism and I think that if players in DC games were presented with the various ammunition they could buy it would make it easier for everyone.  That is exactly why I needed the granular detail in the first post.  We'll see how far I get with it.

 

In the next post I will delve into Armor and how it works vs. firearms.

 

T

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2 hours ago, Deadman said:

I did not include the "light armor piercing" because I am saving that for specific ammunition.  I felt that if it were stated as a function of Soft Body Armor it would  serve as a "House Rule" which could carry throughout the genre.

 

I can see this, but as you stated in your own post, that makes AP Rifle rounds even more effective, as armor hardened with plates would have to be much higher in DEF. Granted, my way limits the ability to have "rifle rounds, light AP rifle rounds, full AP rifle rounds" etc.

 

So what would you rule is a kind of "light AP rifle round" compared to a normal rifle round and/or a full AP rifle round?  (Also, when you state "high velocity rifle round" you are basically saying that any long gun is high velocity compared to pistols, right? Or is it another category... rifle round, high velocity rifle round, light AP rifle round, high velocity light AP rifle round, etc.?? The latter seems WAY too confusing.

 

Also... what category do you consider SMGs to be in? Are they still delivering pistol rounds at pistol velocity, or are they doing more? I don't consider them high velocity or light AP for game purposes, but just wondering about your thoughts.

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1 hour ago, RDU Neil said:

I can see this, but as you stated in your own post, that makes AP Rifle rounds even more effective, as armor hardened with plates would have to be much higher in DEF. Granted, my way limits the ability to have "rifle rounds, light AP rifle rounds, full AP rifle rounds" etc.

 

So what would you rule is a kind of "light AP rifle round" compared to a normal rifle round and/or a full AP rifle round?  (Also, when you state "high velocity rifle round" you are basically saying that any long gun is high velocity compared to pistols, right? Or is it another category... rifle round, high velocity rifle round, light AP rifle round, high velocity light AP rifle round, etc.?? The latter seems WAY too confusing.

 

I would say that Reversed Ogive (THV) Rounds would be Semi-Armor Piercing, which I would say is a +1/4 Advantage.  Full Armor Piercing would be your Hardened Core Rounds designed specifically to pierce armor and would be a +1/2 Advantage.   As you mentioned Armor Piercing would pierce through the amount of defense dictated by the Damage Classes of the attack.  So a .22lr AP round really isn't of that much use as it would pierce only 2 points of resistant defense.  This is probably why most AP ammo are rifle rounds.

 

I am not saying that ANY long gun is a rifle or has high velocity.  I am basing this on the round itself.  As an example there are Lever Action Rifles out there that fire .45 Colt ammuntion out there which would be treated as handgun ammo.  Similarly most submachine guns fire handgun ammo (the M231 notwithstanding which fires 5.56mm).  So it is all based on the round not the firearm at all.  You also cannot define it strictly by Caliber.  .50 Action Express is a very different round than .50 BMG (the former being a very large handgun round and the latter being used in Sniper Rifles and Machineguns).  This is why I have to go back to the actual Energy delivered by that Round.  Thanks to the wonder of the internet all of this information is right at our fingertips.

 

Before some Smart Aleck decides to chime in with the fact that barrel length does affect muzzle velocity.  I will say that in the grand scheme of things it isn't enough to make that big of a difference.  I have heard a 25-75 fps per inch estimation over or under 22" depending on caliber.  Now this may seem like a lot but keep in mind that two "identical" barrels can easily vary by 100 fps.  Take a 230gr .45 ACP Round.  When fired from an M1911 the muzzle velocity is 830 fps.  When fired from the M1A1 Thompson Submachinegun the muzzle velocity increases to 950 fps.  If we plug this into our previous calculations we see that the difference is ~150 joules (477 vs. 625).  While this seems significant they both fit in the 4-5 DC range so while you could increase the damage slightly if fired from a long gun, I wouldn't bother with it.

 

I suppose you could put a small Aid on longer barrel weapons or add a Limitation to the round.  But even by my uber-realistic way of thinking this is more trouble than it is worth.

 

T

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6 minutes ago, Deadman said:

I am not saying that ANY long gun is a rifle or has high velocity.  I am basing this on the round itself.  As an example there are Lever Action Rifles out there that fire .45 Colt ammuntion out there which would be treated as handgun ammo.  Similarly most submachine guns fire handgun ammo (the M231 notwithstanding which fires 5.56mm).  So it is all based on the round not the firearm at all.  You also cannot define it strictly by Caliber.  .50 Action Express is a very different round than .50 BMG (the former being a very large handgun round and the latter being used in Sniper Rifles and Machineguns).  This is why I have to go back to the actual Energy delivered by that Round.  Thanks to the wonder of the internet all of this information is right at our fingertips.

 

Very helpful, and yes, I agree.

 

In this case, it seems like you could make a general ruling of "Joules of particular round > X, round is considered High velocity"... so where is that cut off, in your opinion? It seems to be around 1700 joules (the lowest energy delivered by a 5.56x45 NATO round, which averages 1750-1800)

 

I'd be interested in whether multiple rounds fired from the same rifle have significantly different velocities... so they are within a "range" of velocities, and not always practically the same. Seems likely.

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Unfortunately the answer isn't so easy.  Generally speaking rifles have higher velocity rounds but not always.  There are several High Velocity handgun rounds out there.  The distinction also takes into account the shape of the bullet, rifling and other factors.  Rather than try to apply some sort of cap on the velocity of handgun rounds I would just suggest going to Wikipedia for an overview.  Keep in mind that this list, while long, isn't even close to all encompassing.  The other thing to keep in mind is that there are pistols which fire rifle rounds and vice-versa.  That is why I don't worry about the weapon but go by the round for the distinction.

 

As for whether or not multiple rounds fired from the same rifle have different velocities...absolutely.  When a bullet is manufactured an effort is made to keep everything the same.  The reality is that not everything is always equal.  Now I doubt that the differences are entirely significant but they are there.  It could be caused by the propellant, primer, seating of the bullet in the casing or a number of other factors.

 

Regards,

 

Tom

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6 hours ago, Deadman said:

 

As Zeropoint pointed out the Energy is equal to the Mass multiplied by the Velocity squared (for Joules the Mass must be in kilograms while the velocity is in meters per second) times 1/2.  This means that the Velocity of an object has a larger factor on its energy.  A baseball (.145kg) moving at 50mph (22.352 m/s) and hitting an object would have approximately 36 Joules of energy (~1d6).  If that baseball were moving at 1000mph (447.04 m/s) it would have approximately 14,500 Joules of energy (6d6).  Using these calculations we can easily determine that a 100mph fastball from a pitcher would have about 145 Joules and do about 2 1/2d6 of normal damage so you can see that doubling the Velocity essentially quadrupled its energy.  On the other hand if we doubled the mass of the baseball (.29kg) and kept it moving at 50mph it would have about 72 Joules of energy (~1 1/2d6).  This shows that the mass, when doubled, only doubles the energy.

 

What's interesting is that while kinetic energy is proportional to velocity squared, momentum is only proportional to velocity. This means that as velocity increases, the ratio of momentum to energy changes. In very rough terms, momentum is what knocks the target back, and energy is what blows the target apart. Since humans are used to dealing with things moving at relatively low relative velocities, we have an "intuitive" understanding of things in that regime, but have a harder time with the effects of high-velocity objects. Nowhere is this more apparent than in action movies where people get blown across the room by small arms fire.

 

1 hour ago, RDU Neil said:

I'd be interested in whether multiple rounds fired from the same rifle have significantly different velocities... so they are within a "range" of velocities, and not always practically the same. Seems likely.

 

That depends on what you mean by "practically" and "significantly". Bulk-loaded ammunition has the powder measured by volume, and this is "good enough" for most purposes. A quick look around the internet tells me that muzzle velocities for standard commercial ammunition vary with a standard deviation of about 20 ft/s. A competent handloader putting a little care into the process can expect about 15 ft/s, and someone specifically working for consistent muzzle velocity can expect about 10 ft/s standard deviation. A very skilled handloader putting in a lot of effort might be able to get below 5 ft/s standard deviation.

 

However, such people aren't worried about damage, they're worried about accuracy. How fast a bullet is going affects how long it takes to get to the target, and that affects how much time gravity has to work on it: faster bullets hit the target higher than slower bullets, all other things being equal. For someone doing competitive target shooting at hundreds of yards, the difference between 20 ft/s SD and 5 ft/s SD could be the difference between winning and not even placing.

 

In terms of damage, though, I believe the rule of thumb is that it takes a difference of at least 100 ft/s to notice a change in terminal ballistics. A standard deviation of 20 ft/s could get you a swing that large, but we already roll randomly for damage; I can't believe that even the cheapest ammo would vary enough from round to round to justify rolling a different number of dice.

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So on this subject... looking up .300 AAC Blackout, it says it was developed to deliver 7.62 damage in a M-4 configuration, with size of round enabling similar capacit to 5.56 in a STANAG magazine.

 

But when you look at the joules of the .300 AAC they are equal to or less (depending which chart you read) to the 5.56... but they are still claiming 7.62 stopping power, when that is still almost x2 as much energy.

 

How does that work?

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5 hours ago, Deadman said:

Generally speaking rifles have higher velocity rounds but not always. 

Generally speaking, longer barrels equate to higher muzzle velocities which has a greater effect on delivered energy (as has been mentioned). Do I have a point? Honestly, I'm not sure.

Developing a damage rating for a weapon is less realistic than developing a damage rating for a cartridge. The optimum solution would probably be some cross-reference table indicating both. In either case, I personally feel it would slow things overly much.

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2 hours ago, RDU Neil said:

But when you look at the joules of the .300 AAC they are equal to or less (depending which chart you read) to the 5.56... but they are still claiming 7.62 stopping power, when that is still almost x2 as much energy.

 

How does that work?

First, "stopping power" is poorly understood. Heck, it's not even well defined. We know that all other things being equal, faster is better than slower, and heavier is better than lighter, when it comes to bullets. Beyond that, it gets complicated. People have been arguing about momentum versus energy and penetration versus expansion for decades. Some people will swear that the .45 automatic is the best manstopper available in a handgun. Other people respond by pulling up police shooting reports and insisting that the data shows that with modern ammo, the 9mm has the same percentage of one-shot stops as the .45.

 

So, does the .300 AAC Blackout have the same stopping power as the 7.62 NATO? You tell me how you calculate stopping power, and I'll give you your answer.

 

Second: marketing hype. Precisely because "stopping power" is a nebulous concept, "they" can claim that their round has the same stopping power as the 7.62 NATO and no one can adjust their taped-together safety glasses and say, "Well, actually . . . "

 

My personal thinking is that lethality mainly depends on work done on the target by the bullet, which is to say, energy delivered to the target. That's mainly my physics background coming through, though, and I certainly haven't tested this hypothesis by shooting hundreds of pigs under controlled conditions or anything.

 

Also: are they claiming 7.62x51 NATO stopping power, or 7.62x39 stopping power?

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It is the Soviet x39, which is more around 2100 joules, so not the full 7.62x51 NATO. In that case, it still isn't making the grade, but not as far off... only that AAC is more consistently at the 1800 joules range than standard 5.56 which tends to be 1750 or so.

 

And now I'm trying to figure out how realistically effective the steel core of the 7.62 Soviet is at making the round AP, or is it just increasing damage via fragmentation. Any thoughts on that?

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On ‎6‎/‎19‎/‎2018 at 11:22 PM, Deadman said:

Now on to the next point.  How to address the relative lack of penetration of Handgun Rounds when compared with Rifle Rounds.  My first thought was to adjust Armor Piercing and add it to Rifle Rounds.  While I will probably do this anyway since I don't think that Armor Piercing adequately represents what it does.  Meaning that I think that AP should be based on the attack rather than the Target's Defense.  But I digress, on to the subject at hand.

 

There are currently six levels of Body Armor (I, IIA, II, IIIA, III and IV) though technically Level I is no longer part of the standard.  The first 4 levels are available in Soft Body Armor as follows.

 

Level DEF Protects Against
I 4 .22lr, .32, .38
IIA 7 .45ACP,.40S&W, lv9mm
II 8 .357Mag, 10mm, hv9mm
IIIA 9 .357SIG, .44Mag

 

Given the damage that I posted previously the listed amounts will shut down all but the highest rolls and it is fairly easy to assume that the BODY damage that gets through is due to tissue trauma and internal organ damage.  The GM should adjudicate that the round doesn't actually penetrate.

 

The real problem becomes what to do about Rifle rounds which are much more effective against Soft Body Armor.  More so than the little BODY damage that would get through would indicate.  For this reason I think that as part of the Real Armor Limitation it should reflect that Soft Body Armor only has half of its stated value against High Velocity Rifle Rounds.  This could also be represented by an additional Limitation but my feeling is that it is unwarranted.  If the Rifle Round has Armor Piercing it would go against the modified Defense of the Armor.  Of course doing things this way would also mean that Hard Body Armor would need to be bought to a level that could stop the Rifle Rounds outright.  As I mentioned in another thread Hard Body Armor should be bought using Barrier rules which means that if none of the BODY gets through then no STUN is taken.  We'll go into that on my next post...

 

T

 

I would actually argue that rifle rounds should be Penetrating, not Armor Piercing -- such that they ALWAYS do some BODY unless used against an Impenetrable target.  My thinking here is that it's Killing Damage we're talking about … so the point is doing BODY, not STUN … and a ballistic plate (within a plate carrier) would seem to represent the addition of an Impenetrable component to otherwise soft body armor.

 

I feel this is a simple and clean way to do rifle rounds -- because I don't see them as doing more STUN than pistol rounds in a system where the chosen attack type (Killing Attack) is intended to do BODY (and with Armor Piercing they'd do more STUN in addition to more BODY).  Another option would be to do some kind of Armor Piercing that applies only to BODY … but that's close enough to Impenetrable that I just don't think the wheel needs to be reinvented.

 

 

13 hours ago, RDU Neil said:

 

So on this subject... looking up .300 AAC Blackout, it says it was developed to deliver 7.62 damage in a M-4 configuration, with size of round enabling similar capacit to 5.56 in a STANAG magazine.

 

But when you look at the joules of the .300 AAC they are equal to or less (depending which chart you read) to the 5.56... but they are still claiming 7.62 stopping power, when that is still almost x2 as much energy.

 

How does that work?

Speaking very generally, the stopping power from high velocity rounds comes largely from the generation of hydrostatic shock - a pressure wave developed in the spongy/wet tissues of living objects that is significant enough to damage/destroy tissue that is not actually hit by the projectile generating the wave.  (The same concept applies to grenades -- which are much more lethal in, say, a pool of water in which a target is located … than in air … because of the amplifying effects of water on the pressure wave … since the wave moves more efficiently through dense fluids than through less dense ones.)

 

By comparison, the stopping power from heavier, lower-velocity rounds comes largely from the wound channel generated by the projecticle … and the bleeding effects generated within that wound channel.

 

Thus, you cannot look solely at energy when estimating stopping power -- you must also look at what the energy is used for/doing.  The big .30 cal round for .300 AAC creates a bigger wound channel and more bleeding effects in a target than a 5.56 NATO round … but the 5.5.6 NATO round generates a more significant wave of hydrostatic pressure.  Which round has more stopping power will depend largely on what area of the target was hit … and at what range.  Assuming you're not looking for instant knock-down, the larger .300 AAC round that generates more bleeding over time can actually be used to drop large game (e.g. deer) ethically using a suppressed rifle inside of 75 yards … which is absolutely NOT true of a 5.56 NATO round (suppressed or unsuppressed) at any range -- because it doesn't generate enough hydrostatic pressure to kill large game effectively (i.e. not enough tissue damage to kill the animal humanely, and not a large enough wound channel to drop the animal in a way that has it bleeding out quickly).  This is why 5.56 NATO tends to only be used to hunt things (ethically) that are no larger than coyote or hogs.

 

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3 hours ago, RDU Neil said:

It is the Soviet x39, which is more around 2100 joules, so not the full 7.62x51 NATO. In that case, it still isn't making the grade, but not as far off... only that AAC is more consistently at the 1800 joules range than standard 5.56 which tends to be 1750 or so.

 

And now I'm trying to figure out how realistically effective the steel core of the 7.62 Soviet is at making the round AP, or is it just increasing damage via fragmentation. Any thoughts on that?

My take on the .300 AAC Blackout is that there isn't really enough distinction to matter.  True, it has a heavier bullet with 125gr but the velocity is somewhat lower than a 5.56x45 (2215 fps vs. 2800 fps).  This results in a similar energy output (1840 for the Blackout, 1889 for the 5.56).  Now if you are talking about the Lehigh Defense round, it is much lighter at 78gr but much faster at 2800 fps.  Ultimately it ends up with about the same energy (1841 joules).  I would say that they both do the same damage (2d6k) and given the stopping power you may want to add +1 Stun Multiplier to it (the 5.56 has this to represent the tumbling aspect).

 

My thoughts on the new 7.62x39 BP round is that the steel core would give it at least Semi-Armor Piercing.  If you are using Semi Armor Piercing for all rifles bump it to Full Armor Piercing.  Other than that the ballistics of the original rounds would suggest perhaps a slight bump in DC (perhaps making the initial damage 2d6+1k). 

 

 

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7 minutes ago, Deadman said:

I would say that they both do the same damage (2d6k) and given the stopping power you may want to add +1 Stun Multiplier to it (the 5.56 has this to represent the tumbling aspect).

 

In my game, I ruled it was 2d6+1 based on just an initial "It is supposed to be like the 7.62 Soviet"... and I'm inclined to do that, rather than 2d6 with +1 Stun multiplier. Purely from a "game play" perspective, I find the increased stun multiplier to often scale out of control and give odd results that don't "feel" right.

 

Saying this, and finding great success with rulings that can add body damage, but only up to the max possible with the round (2d6+1 can never do more than 13 body, even if you roll extra dice from Weaponmaster or some such to increase it... this really helps someone roll higher average damage, without scaling damage out of control)... with that in mind, I'm wondering if some ruling with stun could do the same. +1 Stun multiplier can only add Stun up to the max for that hit location... so chest shot with 2d6+1 is a max of 39 stun... so you can multiply x4 with a +1 Stun multiplier, but you max out at 39... head shot it would be 65, etc.   I kinda like that ruling as well. This "only to max of normal damage" is a really nice governor on increased damage adders/multipliers... at least when it comes to adding damage to "real weapons."

 

hmmm... good conversation... if a bit off topic here

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53 minutes ago, Surrealone said:

 

I would actually argue that rifle rounds should be Penetrating, not Armor Piercing -- such that they ALWAYS do some BODY unless used against an Impenetrable target.  My thinking here is that it's Killing Damage we're talking about … so the point is doing BODY, not STUN … and a ballistic plate (within a plate carrier) would seem to represent the addition of an Impenetrable component to otherwise soft body armor.

 

I feel this is a simple and clean way to do rifle rounds -- because I don't see them as doing more STUN than pistol rounds … and with Armor Piercing they'd do more STUN.  Another option would be to do some kind of Armor Piercing that applies only to BODY … but that's close enough to Impenetrable that I just don't think the wheel needs to be reinvented.

 

While I can see some validity in this I would steer away from it as it would then require you to make all Walls, Vehicles and such that are too thick for a rifle round to penetrate, Impenetrable.  My feeling is that by staying with the prescribed body armor and incorporating the imposed limitation on Soft Body armor they will do some BODY on the majority of rolls.  While perhaps not entirely realistic it is in line with the feel of the game.

 

I tend to disagree.  Rifle rounds will do much more STUN than pistol rounds just based on their greater energy.  I also think that if something actually penetrates it would be more painful (i.e. more STUN) than something that doesn't.  In some cases (low STUN Multiplier rolls) you could get a through and through.  While on others you may hit something really important (bones, organs and such).  I guess RDU can get a better sense of this by playing it out.

 

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33 minutes ago, Deadman said:

 

While I can see some validity in this I would steer away from it as it would then require you to make all Walls, Vehicles and such that are too thick for a rifle round to penetrate, Impenetrable.  My feeling is that by staying with the prescribed body armor and incorporating the imposed limitation on Soft Body armor they will do some BODY on the majority of rolls.  While perhaps not entirely realistic it is in line with the feel of the game.

 

Adding a house rule that requires armored walls, vehicle bodies, etc. to be Impementrable if intended to withstand rifle hits would seem to be a hell of a lot less work for a GM than tinkering with every defensive value in the game pertaining to walls, vehicle bodies, body armor, etc. that should be able withstand rifle hits.  i.e. It's quick, dirty, easily understood by all … and involves no math because one doesn't need to play 'what if' games when it comes to rifle hits and their impacts (on armor -- unlike, say, AP, where one has to divide the armor value in half, see if it is enough, then bump it up to withstand rifle hits if it's otherwise too low).

 

But hey, if you want to have to think about the effects of Armor Piercing on every Resistant Defense in the game to make sure you have enough of it where it counts … and if you feel that is less work than using an Impenetrable house rule, then knock yourself out.  Most GM's, however, would probably prefer the easier path and, frankly, I suspect most players would, as well.

 

I raise this because ease of playability is, IMHO, a defining trait among worthwhile alternate/optional rules.  As an example, of why: few people use long term endurance loss or lost REC due to temperature level-induced discomfort because both alternate/optional rules tend to be too much of a pain in the ass to be worthwhile for most GMs/campaigns/players...

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Now I promised that I would do my next installment on Body Armor....

 

Modern Body Armor is difficult to realistically simulate in the Hero System.  Modern Body Armor essentially comes in two types; Soft and Hard.  Soft Body Armor is constructed using very strong fibers which are woven together into a vest or other garment.  I don't want to reinvent the wheel here so instead I am including the Armor Chart from 5e Dark Champions with some expansion.

 

Type of Armor

PD

ED

Notes

Soft Body Armor

 

 

Only Provide 1/2 listed DEF against Rifle Rounds

Ballistic Nylon

 

 

Early attempt at Ballistic cloth.  Used in Flak Vests from 1960s – early 1980s

    Level I-A

3

2

Vulnerable to Bladed Attacks  (-½)

    Level I

4

3

Vulnerable to Bladed Attacks  (-½)

Kevlar (K-29)

 

 

First Generation Kevlar prior to being interwoven with metallic fibers.  In use from 1980s – early 2000s

    Level I

4

4

Vulnerable to Bladed Attacks  (-½)

    Level II-A

6

6

Vulnerable to Bladed Attacks  (-½)

    Level II

7

7

Vulnerable to Bladed Attacks  (-½)

    Level III-A

8

8

Vulnerable to Bladed Attacks  (-½)

Kevlar  (KM2), Spectra, Dyneema, Vectran

 

 

Second Generation Kevlar interwoven with metallic fibers to provide protection vs. bladed weapons

    Level I

5

5

 

    Level II-A

7

7

 

    Level II

8

8

 

    Level III-A

9

9

 

D3O, Carbon Nanotubes, Spider-Silk

 

 

Next Generation Body Armor, Uses Sheer Thickening Fluid and other technologies,

    Level I

6

6

One level up Mobility Chart

    Level II-A

8

8

One level up Mobility Chart

    Level II

9

9

One level up Mobility Chart

    Level III-A

10

10

One level up Mobility Chart

Hard Body Armor

 

 

Used with Plate Carriers to protect vital areas.  Based on Barrier rather than Resistant Protection.

Ceramic/Polyethylene Plates

 

 

 

    Level III

9

9

Ablative (-1/4)

    Level IV

9

9

Hardened (+1/4), Ablative (-1/4)

Metal Plates AR-500

 

 

 

    Level III

8

8

 

    Level IV

8

8

Hardened (+½)

 

So how does this all work?

 

First off I determine the Sectional Coverage.  This means I assign a percentage to each Hit Location and assign a Limitation based on  that.  For example if someone were wearing a standard vest it would cover at least a portion of Hit Locations 9-12 (Shoulders through Stomach).  Given those percentages I come up with the Limitation value.  In this case it would be 48.14% coverage or a -3/4 Limitation.  Personally I have a chart for this which I can post if you like.  Next I, more or less, determine the effective coverage of those locations.  In this case I determine that it covers roughly 80% of the protected areas for an additional -1/2 Limitation.  Then I apply those Limitations to Resistant Protection along with  Focus, Mass, Mobility and Real Armor Limitations to determine a cost.

 

A standard New Generation Kevlar Vest would look like this.

Kevlar Vest (KM2) - Level II:  Resistant Protection (8 PD/8 ED) (24 Active Points); Sectional Defense: Covers Hit Locations 9-12 48.14% (-3/4), Requires A Roll (13- roll; Must be made each Phase/use; -1/2), OIF (-1/2), Side Effects: -1 DCV/DEX Rolls, -2m Movement, Side Effect occurs automatically whenever Power is used (-1/2), Half Mass (-1/2), Real Armor (-1/4)  Cost: 6CP

 

That's right, for the low, low price of 6 character points you are covered....  Well if you get hit in the Chest, Shoulder or Stomach...and roll a 13 or less.

 

Now a couple of things should be mentioned.  First, I am recommending an automatic limitation which comes with Real Armor.  Soft Body Armor only provides half of its Defense vs. Rifle rounds.  Second, you can see that I have added a Minor Side Effect.  Realistically Body Armor slows you down.  So to show that I have included a small penalty to the wearer.  This is to represent the bulk and weight of the armor.  While you don't need to do this it really does help keep your PCs from becoming walking Tanks.

 

That is it for now.  I will get into Hard Body Armor next...

 

T

 

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1 hour ago, Surrealone said:

I raise this because ease of playability is, IMHO, a defining trait among worthwhile alternate/optional rules.  As an example, of why: few people use long term endurance loss or lost REC due to temperature level-induced discomfort because both alternate/optional rules tend to be too much of a pain in the ass to be worthwhile for most GMs/campaigns/players...

 

I agree with ease of use as a key, and probably THE key, criteria for a ruling, but I don't see using Impenatrable or or anything like that as necessary... just use the "hard target reality sniff test".  Just ask, in the moment, is it realistic that a rifle round would penetrate effectively vs. this particular barrier/substance/defense?  If yes... apply the Light AP, or full AP rules as I've defined (subtract half body or full body rolled from defense, then apply damage).  If no... then just apply body as rolled vs. the defense and body of target.


It is that simple in 99% of the cases. Basically my sniff test is "will half AP or AP apply realistically" since these are not "bought powers" but campaign rules. So the caveat is on the rules Light AP or full AP except where it doesn't realistically apply... done.

 

Again, 99% of the time, that is just the rule that flashes through my brain as I make the GM call... go with it and keep gaming.

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