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Atgxtg

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When a source as authoratative as the Army is involved what more do you really want? After all they actually did write the book on the matter. Is Major Plaster's data for penetration at 91m not derived from Army testing? I can't access the notes section but it does look like a standard test set up for the Army. In fact can anyone find non-Army data for these weapons?

Probably not, although I'd have to check his book. Several people do fire such weapons on the firing range.

And manuals generally are more of a "quick and dirty results" than good testing. For instance, if these values are all from single shots, then they are not statistically significant. Also we don't have any data on the age of the ammo.

Chaos stalks my world, but she's a big girl and can take of herself.

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Correction in red mine. Do you suspect that the distribution for the actual bullet is not a normal one? That it would fall all within the first standard deviation for the dice roll? If it did what are we affecting by using dice results outside of that RW distribution? Currently you are already setting the penetration goal with out knowing what the distribution of the actual data is aren't you? Won't most of your penetration figures be greater than the mean and possibly crowding that first deviation break point?

No, I'm saying that the distribution of the actual bullet doesn't match up to the distribution of a dice. For instance with a 6D10 roll there we have an average of 33 and it can vary by +27 points either way. The actual curve of a bullet is probably a lot narrower.

But the "damage" effect on a person does vary widely. Realistically the penetration values for firearms shouldn't vary much, since each round has approximately the same mass and energy. It is just where that energy is being concentrated that makes the big difference.

And the effects of armor are not lineal either. Two inches of armor is more than twice as tough to get though that one inch.

Chaos stalks my world, but she's a big girl and can take of herself.

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So source me baby, I want to learn more!

Well, the one I already posted for starts. But I take it you want a fe more. I'll see what links I can come up with.

This guy here also firea al lot of ammo to see what it will penetrate: The Box O' Truth - The Box O' Truth

Yes, it is a bad thing. Because there is nothing to support the data. We don't know which test "Gary" [pulled his data from, or how old it is. Or if the data is correct. For all we know the reason why the penetration ftlatlines against concrete could be a simply cut & paste error.

Sorry about the misnomer. :o

Sure. Lets look at the .50 cal, since it seems to be our "test model" at the moment. Now all the sources we've used so far indicate that a .50cal will reliably (at in over 97% of the time statistically) penetrate 10mm (17AP on my chart, for an example) of steel at up to 600m. So for the bullet to reliably penetrate 10mm consistently, the damage would have to consistently be higher than 17. So that means than in the game the .50 cal will kill every time.

Now if we look at the performance of less powerful weapons we run into the same problem. For instance a 7.62 bullet that will go through a NIJ Class II vest will do so constituently. But a class II vest will stop most pistol rounds. So that would mean that a 7.62 would need to have a minimum damage rating higher than most pistols max damage rating.

Another thing is that armor protection increases at better than a linear rate. The whole, subtract APs from damage does work out. For instace, if a bullet can penetrate 2" of armor and goes through 1", it actually has most of it's energy.

Yes, but I working with what we got. I'm not reworking all of BRP. Oh, and I did upload a table in the downloads section for a different way to handle damage, instead of losing hit points you take injuries. It might be just the thing to handling big damage increases in BRP.

There are some RPGs out there that do take a different approach and give somewhat better results for firearms, Timelords, Morrow Project Delta Force, James Bond, CORPS, and EABA all spring to mind. Timelords in particular does a lot of the stuff that you seem to want. For instance look at the damages that the firearms do:

[table].22LR| :9

9mmP |12

.44M|17

5.56N|27

7.62N|30

12.7mm|56[/table]

While firearm damage (and penetration) is consistent (it does drop off at range), the effects on a human are not, since the game uses 31 hit locations, and a D10 to vary the results.

But BRP is set up a certain way, and throwing it all out and rewriting everything from scratch is a whole different project.

Chaos stalks my world, but she's a big girl and can take of herself.

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What about returning to Penetration Value?

I applaud this effort, but it seems like we are trying to model the real world a bit too closely. More accuracy good; more complexity in the system (ie playability) bad. :)

Penetration Values

0 Pistol / ball ammunition

1 Small Cal. spindle ammunition (roughly 4-6 mm), or large or magnum ball

2 Medium Cal. spindle (roughly 7-9 mm)

3 Large Cal. spindle (those few between 10 and 12 mm)

4 Small Cannon :D (.50 BMG, 12.7x108mm, 14.5... etc)

etc.

Each substance would then have a Hardness which the penetration would match against. Armor grade aluminum and steel having noticeably higher Hardness than their non-armor counterparts.

Each weapons "Damage" would remain similar to what it is now, perhaps narrowing the overall range a bit, and allowing for the retention of Specials and Critical hits against soft targets.

Basic values for penetration and damage would be based on round, modified by weapon for penetration, damage, and range. Different round types (AP, SLAP) would modify penetration or damage up or down, as would "accessories" like silencers/suppressors.

Perhaps this IS what your talking about in the end. It just seems like a great deal is being passed back and forth here with no consensus in site!

Though if you are simply having fun in the debate <stands aside> then by all means continue! :D

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I would just like to state, as one firmly grounded in reality (I couldn't type that with a straight face), that this thread is likely being monitored by the government in order to create new super-weapons.

The level of detail regarding firearms is going far beyond what the thinktanks the government gathered to design M16's before Vietnam could begin to even fathom.

Guns, Bullets, and thick metal plating everywhere is/are rejoicing at the sheer amount of attention they are receiving in this thread. They're now forming a political party.

Oh crap. Did you hear that?

You people have fondled the concept of Arms and Armor so much that they've manifested as a Chaos Gods in the Warp. Great job, guys. Way to go.

"Men of broader intellect know that there is no sharp distinction betwixt the real and the unreal..."

- H.P. Lovecraft

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Yes, it is a bad thing. Because there is nothing to support the data. We don't know which test "Gary" [pulled his data from, or how old it is. Or if the data is correct. For all we know the reason why the penetration ftlatlines against concrete could be a simply cut & paste error.

The data matches that found in FM-23-65 Browning Machine Gun Caliber .50 M2, HB in chapter 1 table 1-5 and 1-6. Table 1-6 supports the web version not being a simple cut and paste error as the information is the same but in a different format.

With all fairness the information presented in Maj. Plaster's book concrening penetration at 91 m, fits all of the parameters you have listed. There are no footnotes or attributions to indicate where the information came from, or how old it is. While the Box o' Truth is a fun site it too has problems in pertaining to our present discussion. There is no comparative data for multiple ranges, the ranges shot at are extremely short and the number of rounds are very small. While it is illustrative of the reasons to buy a brick house it does little to help plot armor values for anything we did not already know would be pretty low on APs.

In short I don't think that you have proven your points that the military data is somehow suspect or that the web versions inaccurately report it. Your own sources you have put forward do not invalidate any of the information in the military sources so I fail to see why it should not be used.

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I would just like to state, as one firmly grounded in reality (I couldn't type that with a straight face), that this thread is likely being monitored by the government in order to create new super-weapons.

The level of detail regarding firearms is going far beyond what the thinktanks the government gathered to design M16's before Vietnam could begin to even fathom.

Guns, Bullets, and thick metal plating everywhere is/are rejoicing at the sheer amount of attention they are receiving in this thread. They're now forming a political party.

Oh crap. Did you hear that?

You people have fondled the concept of Arms and Armor so much that they've manifested as a Chaos Gods in the Warp. Great job, guys. Way to go.

Not really. Go take a lotk at the info on armor penetration formulas. Or all the ballistics formulas and data out there.

Its a very complex subject. It all comes down to what degree of detail you want, and how much error you can accept and where.

I did up the table to try and fit the data points given in BRP and to make something compatible with it.

Anything with more detail accuracy would require throwing out the data in the book. Thats okay for something down the road, but I'd like to at least wait for the book to come out and read it before doing any sort of rewrite.

Chaos stalks my world, but she's a big girl and can take of herself.

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What about returning to Penetration Value?

I applaud this effort, but it seems like we are trying to model the real world a bit too closely. More accuracy good; more complexity in the system (ie playability) bad. :)

Penetration Values

0 Pistol / ball ammunition

1 Small Cal. spindle ammunition (roughly 4-6 mm), or large or magnum ball

2 Medium Cal. spindle (roughly 7-9 mm)

3 Large Cal. spindle (those few between 10 and 12 mm)

4 Small Cannon :D (.50 BMG, 12.7x108mm, 14.5... etc)

etc.

Each substance would then have a Hardness which the penetration would match against. Armor grade aluminum and steel having noticeably higher Hardness than their non-armor counterparts.

Each weapons "Damage" would remain similar to what it is now, perhaps narrowing the overall range a bit, and allowing for the retention of Specials and Critical hits against soft targets.

Basic values for penetration and damage would be based on round, modified by weapon for penetration, damage, and range. Different round types (AP, SLAP) would modify penetration or damage up or down, as would "accessories" like silencers/suppressors.

Perhaps this IS what your talking about in the end. It just seems like a great deal is being passed back and forth here with no consensus in site!

A penetration stat isn't a bad idea. Personally, I'd like to either rate it in incches/cm/mm steel. Or maybe flesh.

Then we would have to try and work out values for other materials. Interestingly enough, I don't think that has any effect on the table per say. I just think I need to adjust the modifiers for different materials as I get more data.

Case in point, due to this debate I've been doing some surfing on information about the ballistic properties of concrete, a topic that I previously had not dwelled upon for long. I've been finding out that there are different grades and that some newer concretes are specifically made to be resistant to bullets.

At this point I'm thinking that concrete is about a -10, and that reinforced concrete is about a -5.

Though if you are simply having fun in the debate <stands aside> then by all means continue! :D

That is more of something that had been discussed in email flowing over onto the forum. I showed Joseph Paul, and a few others, the table before I posted it here or used it in the BRP Quick Vehicle Rules 4.2. He didn't like it then, and he doesn't like it now. Nor will he.

If he can find something that works better and still fits the data points in BRP I'd be glad to adopt it.

If he wants to do something different, that's fine too. My goal was to write something compatible with BRP that people could use. Not replace the game system.

Chaos stalks my world, but she's a big girl and can take of herself.

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The data matches that found in FM-23-65 Browning Machine Gun Caliber .50 M2, HB in chapter 1 table 1-5 and 1-6. Table 1-6 supports the web version not being a simple cut and paste error as the information is the same but in a different format.

With all fairness the information presented in Maj. Plaster's book concrening penetration at 91 m, fits all of the parameters you have listed. There are no footnotes or attributions to indicate where the information came from, or how old it is. While the Box o' Truth is a fun site it too has problems in pertaining to our present discussion. There is no comparative data for multiple ranges, the ranges shot at are extremely short and the number of rounds are very small. While it is illustrative of the reasons to buy a brick house it does little to help plot armor values for anything we did not already know would be pretty low on APs.

In short I don't think that you have proven your points that the military data is somehow suspect or that the web versions inaccurately report it. You own sources you have put forward do not invalidate any of the information in the military sources so I fail to see why it should not be used.

All data should be suspect.

Your orginal point was that a .50 cal won't penetrate 6" of concrete because Gary's say's it wont. And Gary's has that @ 200m.

None of the info pulled out by either of us is conclusive (concrete? :)). THat is just the point.

Or do you dbout that a .50 cal will penetrate more at 100m than at 200m.

Compare both sets of data and combine to one table:

[table] Range| Steel|Clay|Sand|Concrete

90m|46mm|1067-1626mm|610-914mm (dry/wet)|229mm

200m|25.4mm|711mm|356mm|51mm

600m |17.6mm|686mm|304mm|25mm[/table]

Now putting that in AP terms on the table we get:

Compare both sets of data and combine to one table:

[table] Range| Steel|Clay|Sand|Concrete

90m|26AP|44-46AP|41-43AP (dry/wet)|35AP

200m|23AP|42AP|38AP|27AP

600m |20AP|42AP|37AP|23AP[/table]

Note that except for concrete, the relative penetrating ability between materials is rather consistent. Clay is about -20 AP behind steel (that is a bullet that will penetrate 26 APs of steel will penetrate about 46 APs of clay), Sand is about -16. All the data falls within 2 points except concrete.

With concrete we get an average of -5, with the 100m range being 4 more and the farther ranges being 1 and 2 less. If we assume that the solid concrete used at 90m is solid, and that the other concretes have been reinforced, we'd get about -7 AP for solid concrete and -4AP or so for reinforced.

All in all I think the table holds up pretty well.

Chaos stalks my world, but she's a big girl and can take of herself.

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Not really. Go take a lotk at the info on armor penetration formulas. Or all the ballistics formulas and data out there.

Its a very complex subject. It all comes down to what degree of detail you want, and how much error you can accept and where.

I did up the table to try and fit the data points given in BRP and to make something compatible with it.

Anything with more detail accuracy would require throwing out the data in the book. Thats okay for something down the road, but I'd like to at least wait for the book to come out and read it before doing any sort of rewrite.

I was just inserting my insipid little joke to help lighten the 12 ton topic... I meant zero offense!

"Men of broader intellect know that there is no sharp distinction betwixt the real and the unreal..."

- H.P. Lovecraft

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I was just inserting my insipid little joke to help lighten the 12 ton topic... I meant zero offense!

None taken.

Frankly I'd love to get more data to work with when designing something. The more data points the better I can make the formula.

I think I understand most of Joseph's Pauls complaints. I just don't think that those isses can be addressed by something that is trying to be compatable with the numbers given in BRP.

If we were to throw out the values and build from the ground up it could be adressed but then it wouldn't be compatible.

One idea I've been toying with is a sort of damage class system with the damage ratings on a sclae like the SB5 demon chart: 1D2/1D4/1D6/1D8/1D10/1D10+1D2(2D6)/1D10+1D4/1D10+1D6 (2D8)/1D10+1D8/2D10, etc.

Then treat armor as a DC shift. That way we could make armor penetration consistent. So, if a 7,72 was DC8 (2D6+2 is about the same a 1D10+1D6) and an M113 APC could stop it, it would have a 8-9 DC reduction. If a .50 cal did DC14 (2D10+1D8 about the same as 4D6+3) so if a .50 cal was fired at a M113, anyone inside who was hit would take DC6/2D6 (DC14-DC8=6) damage.

It's simple, easy and eliminates several of the problems between weapons, armor, and characters. You never have to worry about a gun not penetrating what it should, or a gun punching though something it can't.

Chaos stalks my world, but she's a big girl and can take of herself.

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All data should be suspect.

Your orginal point was that a .50 cal won't penetrate 6" of concrete because Gary's say's it wont. And Gary's has that @ 200m.

Gary's has what at 200 meters? The way you have written this makes it sound like you are saying that the data from FM 23-65 supports 6"+ penetration in concrete which it does not.

None of the info pulled out by either of us is conclusive (concrete? :)).
LOLOLOLOL!

Or do you dbout that a .50 cal will penetrate more at 100m than at 200m.

All data should be suspect. :lol:

Given that some rounds do not automatically penetrate more at shorter ranges I would have to say that it is a real possibility. I am skeptical that any of the .50 cal Ball rounds will do 4 times as much damage at 91 meters as they do at 200. The data from Maj. Plaster was for AP and we don't have AP vs concrete data at 200, 600, and 1500 m. Does the table work if you multiply by 4 for the 200 and 600 meter figures? I get 37/35/31 AP that way. If you are subtracting 10 for concrete that becomes 27/25/21. Wow that is still going to suck up all of the normal 4d6+3 roll so what kind of divisor or bonus is reasonable? How hot is that round when it comes through the other side? Maj. Plaster obviously expects that an exiting AP round will carry enough velocity to still wound the target. It may be that the spalling is what is doing the wounding too.

Do you realize that you have mixed the data for both Ball vs concrete with AP vs concrete and AP vs the other materials? That may be skewing the results.

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Joseph Paul

"Nothing partys like a rental" explains the enduring popularity of prostitution.:eek:

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I was just inserting my insipid little joke to help lighten the 12 ton topic... I meant zero offense!

Heck this isn't heavy at all. We are just making sausage and that isn't for the squeamish.

Atgxtg has done an awful lot of work to fit known data to the examples given in BRP so far. My hat is off to him.

SDLeary- I like the pentration factor idea and have advocated it myself. TIme to play with the numbers now. And yeah I am having a good time still.

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Joseph Paul

"Nothing partys like a rental" explains the enduring popularity of prostitution.:eek:

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Gary's has what at 200 meters? The way you have written this makes it sound like you are saying that the data from FM 23-65 supports 6"+ penetration in concrete which it does not.

What I'm saying is that penetration @ 200m isn't the same as penetration up close. SO just because it doesn't penetrate 6" @ 200m doesn't mean it won't at closer ranges.

Given that some rounds do not automatically penetrate more at shorter ranges I would have to say that it is a real possibility.

The rounds that don't are light rounds that break up on impact. The 5.56 NATO and, to a lesser extent, the 7.62 NATO.

I am skeptical that any of the .50 cal Ball rounds will do 4 times as much damage at 91 meters as they do at 200.

Damage? or penetration? As far as penetration goes, don't be so skeptical. The change in energy is proportional to the square of the change in velocity. Also we still don't know what kind of concrete the army used in those tests. For the other test, mentioned and the statement about shooting through building material specifically mentions reinforced concrete. That makes a big difference, since reinforced concrete is many times stronger than solid concrete as used by the Major.

The data from Maj. Plaster was for AP and we don't have AP vs concrete data at 200, 600, and 1500 m.

The M2 round used in the tests @ Gary's was an AP round.

Penetration capabilities of a single .50 caliber M2 AP round fired from a 45-inch barrel.

So we do have data for an AP roundagainst conrete. I suspect it's against reniforced concrete.The major may be using the same ammo.There are a couple of .50 cal. AP rounds so he could be using the M33. However since the M33 has less penetration that the M2, so if anything the numbers would be higher.

Does the table work if you multiply by 4 for the 200 and 600 meter figures?

Multiply what? The thickness of the wall or the Energy of the bullet. In you increase the thickness of the wall by four then you will increase the APs.

Also the drop off of a bullet's energy is not a nice simply -x every y meters or twice the distance half the energy.

Here is a link to a ballistics table for a .50 cal round. It's a different round, but is good for a rough idea.

Ballistic tables 50 bmg

I get 37/35/31 AP that way. If you are subtracting 10 for concrete that becomes 27/25/21. Wow that is still going to suck up all of the normal 4d6+3 roll so what kind of divisor or bonus is reasonable?

Actually 4d6+3 can get though 25 and 21 APs. Just not much can get though. That is the problem with a wide damage roll, that I've raised before. In order to penetrate something reliably the damage has to be set high enough so the round will penetrate.

How hot is that round when it comes through the other side? Maj. Plaster obviously expects that an exiting AP round will carry enough velocity to still wound the target. It may be that the spalling is what is doing the wounding too.

Spauling.? No, since it is in a book about sniping I don't think he is expecting sauling to do it. Especially from a .50 cal. And I doubt the .50 has much energy left after penetrating that 9", otherwise it would have gone a little deeper.

Do you realize that you have mixed the data for both Ball vs concrete with AP vs concrete and AP vs the other materials? That may be skewing the results.

No I didn't. You didn't realize that the round listed in Gary's was the M2 AP round.

Chaos stalks my world, but she's a big girl and can take of herself.

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Quote:

Originally Posted by Joseph Paul viewpost.gif

The data from Maj. Plaster was for AP and we don't have AP vs concrete data at 200, 600, and 1500 m.

The M2 round used in the tests @ Gary's was an AP round.

Quote:

Penetration capabilities of a single .50 caliber M2 AP round fired from a 45-inch barrel.

So we do have data for an AP roundagainst conrete. I suspect it's against reniforced concrete.The major may be using the same ammo.There are a couple of .50 cal. AP rounds so he could be using the M33. However since the M33 has less penetration that the M2, so if anything the numbers would be higher.

________________________________________________________________

I have a problem with what you are asserting here. It is obvious to me that on Gary Cooke's site and in FM 23-65 there are two tables that are explicit about what they are firing. Those tables contradict what you have stated.

Penetration capabilities of a single .50 caliber M2 Ball round fired from a 45-inch barrel.

Range .............Sand .....................Clay ...................Concrete

219 yd (200 m)14 in (355.6 mm) .....28 in (711.2 mm) 2 in (50.8 mm)

656 yd (600 m)12 in (304.8 mm) .....26 in (660.4 mm) 1 in (25.4 mm)

1,640 yd (1,500 m)6 in (152.4 mm) .21 in (533.4 mm) 1 in (25.4 mm)

Emphasis mine. This is the table that includes the data for concrete. Notice that it specifies M2 Ball ammo. While M2 Ball has a steel core it is not the same thing as the M2 AP round. It's function is layed out in the description of the round: " The cartridge is intended for use against personnel or unarmored targets."

Penetration capabilities of a single .50 caliber M2 AP round fired from a 45-inch barrel.

Range.............Armor Plate (homgns) Armor Plate (f-h) Sand ...................Clay

219 yd (200 m)1.0 in (25.4 mm) --------0.9 in (22.9 mm) --14 in (355.6 mm) --28 in (711.2 mm)

656 yd (600 m)0.7 in (17.8 mm) --------0.5 in (12.7 mm) --12 in (304.8 mm) --27 in (685.8 mm)

1,640 yd (1,500 m)0.3 in (7.6 mm) ----0.2 in (5.1 mm) ----6 in (152.4 mm)----21 in (533.4 mm)

Emphasis mine. This is the table you referenced. It specifies M2 AP and has no data for concrete even though the description of the round states: "The cartridge is for use against light-armored or unarmored targets, concrete shelters, and similar bullet-resisting targets."

Here are the tables from FM 23-65:

Miscellaneous Data. Table 1-5 lists the maximum penetration in inches for an armor-piercing cartridge fired from the 45-inch barrel (muzzle velocity, 2,935 feet per second), which in some cases may enhance the leader's selection of targets to engage.

tab1-5.gif

Table 1-6 lists the maximum penetration in inches for a ball cartridge fired from the 45-inch barrel (muzzle velocity, 2,935 feet per second):

tab1-6.gif

Here are the relevant addresses to check: FM 23-65 Chptr 1 Introduction

and

.50 Caliber Browning (12.7 x 99 mm) Ammunition

I understand that fitting real capabilities into what we know of BRP so far is a tough job. It isn't made any easier by calling a tail a leg which is what you seem to have done here.

Edit :Piffle! I need to learn how to make good looking tables 'cause I can't seem to import them from Excel to here!

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Below is a table with the percentage chance for our 4d6+3 .50 cal to pentrate different materials as depicted by Atgxtg's Armor Table. It shows the percentage chance to roll greater than the material's APs or higher.

Material ammo AP % to exceed AP

concrete 9" @91m AP 25 AP 1.16%

concrete 2" @200m Ball 17 AP 44.73%

concrete 1"@600m Ball 11 AP 94.60%

1" steel@200m AP 21 AP 15.90%

Sand 14" @200m ball or AP 22 AP 9.72%

This is not attenuated for ranges or the use of AP ammo (the ammo heading shows what was used in firing tests but the damaged roll wasn't changed) so it is a little messy. So while it is true that you can roll high enough to pentrate some of these materials it certainly is not the way to bet. Which is unfortunate since soldiers are taught that their weapons will penetrate these materials at theses thicknesses and do so with ease. They are certainly taught to take cover behind material that is thicker than this, see Survivability FM 5-103.;)

I think I would be happy if the weapons functioned in the 80% range of their real capabilities.

Well Excel tables do not transfer well! Corrected by hand.

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Below is a table with the percentage chance for our 4d6+3 .50 cal to pentrate different materials as depicted by Atgxtg's Armor Table. It shows the percentage chance to roll greater than the material's APs or higher.

Material ammo AP % to exceed AP

concrete 9" @91m AP 25 AP 1.16%

concrete 2" @200m Ball 17 AP 44.73%

concrete 1"@600m Ball 11 AP 94.60%

1" steel@200m AP 21 AP 15.90%

Sand 14" @200m ball or AP 22 AP 9.72%

This is not attenuated for ranges or the use of AP ammo (the ammo heading shows what was used in firing tests but the damaged roll wasn't changed) so it is a little messy. So while it is true that you can roll high enough to pentrate some of these materials it certainly is not the way to bet. Which is unfortunate since soldiers are taught that their weapons will penetrate these materials at theses thicknesses and do so with ease. They are certainly taught to take cover behind material that is thicker than this, see Survivability FM 5-103.;)

I think I would be happy if the weapons functioned in the 80% range of their real capabilities.

Well Excel tables do not transfer well! Corrected by hand.

So would I, but that is a fundamental problem with the overall method that BRP handles weapons and armor. If we set the APs low enough so that a .50 cal would get through 1" of steel most of the time, then we would have to set 1" steel plate at about 12-15AP. THat would make 1" steel numberable to 7.62mm and 5.56mm.

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Just jumping in here at the tail end of the thread.

What about the armour penitration of the weapon/projectile?

Cthulhu Rising (Futuristic CoC in an 'Aliens' like setting) give most of it's firearms an armour penitration value as well as damage. APV is the amount of armour that the wepon ignores before rolling for damage

I am not sure if Zero edition has anything like this in it but works really well.

Using some of the previous examples you could give your .50 cal AP round 20 points of armour penitration. At base range this will happily sail though your 21 points of 1" steel.

You can use the range incriment system to reduce APV over range much the same way as you do chance to hit which I think is something like 1/2 at double base range and 1/4 at longer.

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Using some of the previous examples you could give your .50 cal AP round 20 points of armour penitration. At base range this will happily sail though your 21 points of 1" steel.

You can use the range incriment system to reduce APV over range much the same way as you do chance to hit which I think is something like 1/2 at double base range and 1/4 at longer.

That's not a bad idea. I don't have Cthulhu Rising. I was thinking of adding an AP mod and a stopping power mod (penalty to penetration, but extra damage after armor).

How does APV work in regard to damage an/or higher APs or armor? For instance if a wea[pon has a APV of 20 like in your example, if it rolls 25 damage, would it penetrate 20, 25, or 45?

Chaos stalks my world, but she's a big girl and can take of herself.

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APV is a value of armour that it ignores. This is a fixed value and is sperate from damage.

E.g. if a person with 4pts Armour is shot with a round that does 2d6 damage and has 6pts of APV then 6 out of the 4 pts of armour is ignored (all in this case) and they take just 2d6 damage.NOT 2d6+2. The extra armour penetration is wasted.

The same weapon (2d6 +APV(6) ) against the person in 10pts of battle armour, 6 out of the 10 pts of armour is ignored leaving the person with 4pts armour which helps against the ramaining 2d6 damage.

Cthulhu rising has hit locations so damaged is dialed down slightly on weapons.

Although it doesn't specify it in any rules I would suggest that if a round has to go though two sets of armour, such as a person in body armour standing behind a wooden wall, the round keeps its remaining APV ONLY if it uses less than half penetrating the first armour, otherwise the APV drops to zero.

This would fromt he round sheading velocity and starting to tumble when it encounters enough resistance.

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Thats for the explanation. I'll see if I can incorporate that into what I have now.

The major worry will be weapons penetrating too much due to APV. A doubling is +4 on the table, so to double something penetrating power just add 4 APV.

Since AP rounds often have 150% or200% the penetrating power of the standard round, then +2 and +4 might be possible as standards. I'll have to DL some weapon stats for C Rising and see what values the weapons get as well as some ratings for barriers.

Chaos stalks my world, but she's a big girl and can take of herself.

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  • 2 weeks later...

I think APV sounds like an excellent solution. Also, given the structure of the BRP rules, you could simply encapsulate it as an "Optional Rule" (ie like the Strike Rank column in the Weapons Tables) and you'd be good to go. It feels lightweight, elegant, (ie very "BRP"), and it sounds like it solves the problem to a great extent.

Cheers,

Sarah

"The Worm Within" - the first novel for The Chronicles of Future Earth, coming 2013 from Chaosium, Inc.

Website: http://sarahnewtonwriter.com | Twitter: @SarahJNewton | Facebook: TheChroniclesOfFutureEarth

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