Joseph Paul

Set up a saved search on Ebay. That way you can see the stuff show up with out having to spend time trolling for it. You would be surprised how often stuff that you now is a high ticket item goes for fairly cheap. Also check other bookseller services like Alibris.

Empty- I like the bubbl.us site for brainstorming some ideas.

Joseph Paul

Well I haven't logged out in along time so that may be some of it.

As the T&C are mutable it may not have been there when I registered. Or it may have and both Triff and I missed seeing it. How do I access the T&C now to review it?

Oh and just for the record I oppose making the forums a creative commons license. Why? Because I don't understand how it can bite me in the ass yet.

Thanks for removing it Triff.

They are? Where does it say that and how did I miss it?

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.

Quote:

Originally Posted by Joseph Paul

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.

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):

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!

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.

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? ).

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

All data should be suspect.

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.

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.

1) I do have some sources for the penetration of concrete.

So source me baby, I want to learn more!

So far all, you've brought up was Gary's.

You still say that like it is a bad thing. Would it help if I attached the appropriate FMs? Do you have differing data at the 200, 600, and 1500 meter test points? And by the way I don't know who this John Paul guy is. My name is Joseph.

No, not statistically. <snip> So if you set the minimum die roll so that you would get this vaule, it ends up messing the results against people.

Please illustrate what you mean by a minimum die roll vs AP of 17. I think we are talking about different things.

As for killing characters I do indeed grasp what effect higher damages will have on them. However I agree with you that the present manner of deciding wounding and death does not tally with the reality of forensic ballistics. I can see a system where a round that doesn't hit something vital is mostly wasted. It may cause some small HP loss or bleeding but not an insta-kill. Under such a system you could have proper results for both endeavors- anti-personel and anti-material.

They will perform with 3 standard deviations of the norm over 96% of the time. But the norm for the actual bullet and the norm for the die roll are two different things. For instance a standard deviation for 6D10 is over 7 points. So 1 standard deviation is a 14 point range. That is what will come up 68% of the time and to match that up with real weapon data we would need enough of a sampling for penetration data to get the actual spread of the real weapon.

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?

Being on the internet doesn't make information correct though. Especially official US Army documents. Generally the Army is very conservative about their performance data.

I'm not impugning you source, just your claim that the "Army" disagrees with me. You made it sound as if the US Army stopped by, looked at the data and went "nope, no way."

Sorry for the hyperbole. Would smilies have helped?

Instead you looked at one source, took their data as gospel and then presented it as if you had an Army's to back up your judgment.

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?

Now if the energy from a .50 cal drops off between 600m and 1500m (and it does) then the penetration for concrete should drop off. But it doesn't. The bullet penetrates just as deep into concrete at 1500m as at 600m, and that is all that the table covers, penetration.

Could this be an example of rounds performing sub-optimally at certain ranges? The 7.62 has a problem with sand below 200 meters for instance. Closer is not always better. I don't know, maybe you do, what the actual test parameters are for any of these figures. It may very well be that at 600 meters the .50 can zip right through 2" but not 3" while at 1500 m it is barely making it through 2" at all. I suspect that for the discrete materials like steel, brick, and concrete the test is against a sample of set thickness and not a monolithic block sample.

And the penetration value against concrete does drop off according to the test.

You have numbers for this? I would like to see the relationship.

Hey looks like you found a source for penetrating 6+ inches of concrete! Congratulations! I searched that book with Amazon for a while but couldn't find anything on what rifle or round was being used. Did you see the figures for 5.56 and 7.62 at 100 yards?

If I understand the table in this post you give what the straight APs are from the Armor table for thickness and then give the material modifiers, right? If so why does everything have 25 APs? Do you realize that at 25 APs a 4d6+3 .50 cal fails 98.84% of the time?

Major Plaster does state that they are AP rounds so we could introduce a divisor or AP modifier to help with penetration. As the author points out what is hard is knowing how much 'oooomph' is left though. Hmmm.

Joseph Paul

Originally Posted by Joseph Paul

It doesn't look like the Army agrees with that. Penetration of concrete with M2 ball ammo is 2" at 200 meters. There appears to be a table giving the following in a FM- At 25 deg oblique and 100 m it takes 300 rounds to breach a 24" thick reinforced concrete wall and at 200 m it takes 1200. What is rebar reinforcement worth?

Which Army? If you are going to bring an Army in to disagree with me could you be specfic and yet me know who is disagreeing with what, or if you've just goggled up Garry's Infantry Reference Guide.

Why the US Army of course! The values I am refering to come from the appropriate Field and Technical Manuals for the weapons concerned. They just happen to have been compiled at Gary’s site but I have been tracking them down to cross check. And if you want to impugn a source because it is stored on a server you should be prepared to state why it is suspect. I find the “if its on the internet it can’t be valid” rejoinder ridiculous in the face of so much correct information being digitally stored.

Also, I did say cement, not concrete, those rocks would make a difference, and rebar is a who different baby-especially if you hit the metal. That reinforcement is like a mesh that helps to spread out the impact.

Do you have a cite for that figure for cement? I can’t find anything on cement alone. The Army manuals always reference concrete. I don’t know if they know there is a difference or if ‘concrete’ is supposed to cover both. I agree that the rebar makes a heck of a difference. I threw it in for completeness and to show that it is expected to be breached with concentrated, close range fire running into the hundreds of rounds. It sets an upper bound on what can be achieved.

Quote:

Originally Posted by Joseph Paul

SLAP ammo appears to do about a third better in armor than M2 AP(I am presuming homogenous plate) so it may do about 3" of concrete but I don't have a source for that.

That can depend on what gun you fire it from, and which version of SLAP. The regular .50 cal round have been tweaked over the years so that it now can get though an inch of steel, a lot more than it could a few years ago, when everybody was designing things based ion it being able to penetrate a half inch.

The stats on the SLAP and SLAP-T are pretty much the same. Do you know of a different one? My understanding is that the SLAP rounds are verbotten in the M82 and M107 rifles (problem with them coming out the side of the barrel (!)) so that leaves the M2 HB as the current weapon that can fire them.

Given the dramatic improvement of the SLAP round fired from the M2HB I extrapolated at what it could do in concrete. I could be wrong and I can’t find a source for SLAP penetration in concrete.

Quote:

Originally Posted by Joseph Paul

1" of concrete= Ln25.4*5.77-11? So 7.66 round up(?) to 8?

Round to the nearest.

Quote:

Originally Posted by Joseph Paul

.50 I am told will do 4d6+3 so 17 on avg. 2" of concrete should be about 12 AP so the .50 will still penetrate. The 7.62 does 2d6+3 (?) avg 10 pts. Hmm consulting my sources shows that the army believes that 7.62 mm *will* do 2" of concrete. How odd, I wouldn't have thought so.

As I wrote at the start of this I didn't go with average damage but with close to top end. The reason being that the spread for firearm damage is so wide, if I went with the average values then most bulletes would be able to get though some armors half the time.

For instance if the 50 cal can get through 25.4mm of steel at 200m do we set 25.4mm at the 17 average damage in BRP zero? or do we set it at the low end to be sure that it will always do so, and thus say that 25.4mm is equal to 6 points? Or do we set it near the top? I went with the latter. While it will mean that there will be times when a 50 cal won't penetrate something that it should, the other methods allow for lighter weapons to penetrate things that they shouldn't.

The .50 cal round that does that is the M2AP round. It uses a tungsten-chrome steel core rather than just plain steel one in the M2 Ball round. Why not give it an armor divisor or an amount of AP it bypasses to represent it’s special qualities rather than making it the basis of performance?

I believe that we should set the values so that the performance bears some close resemblance to what can be proven to be done. If we want to make the concious and informed decision to degrade or inflate the performance of the weapon(s) for genre or story reasons we can do that for the specific genre or story.We have discussed the problem you present hereand the solution I advocate is to spread the data points farther apart so that you do not get the overlap in performance.It means that a .50 will do a lot more dice of damage but that you won’t get less powerful rounds doing things they shouldn't.

If the 7.62 penetrates 2" of concrete per your source (I'm not so surprised, since I don't think it was shooting at something 200m away for the test)

It was and that is what is listed in table 7-3 of FM 3-06.11 for 25, 100, and 200 meters.

then if the 7.62 does 2d6+4 (the bolt action rifle), then do we set 2" of concrete at 10AP? And if we do now the assault rifle (2d6+2) will be able to punch though 2" of concrete 28% of the time. And if we did that, the .50 cal which your sources (I assume Gary's) state can't penetrate 2" of concrete will now do so pretty much every time at 4D6+3.

Whoa there Tex! You have got it all wrong, please go back and read it again. I claimed that there is no agreement to your unsourced assertion that the .50, in any configuration, would penetrate 6” of cement not that it couldn’t penetrate 2” of concrete. So lets look at your argument again. You claim that the spread for firearm damage is wide. I am assuming that you mean a specific die roll has a lot of variability to it, yes? Well that becomes less of a concern if the data points are spread out farther. I have discussed with you before the desirability of making firearm damages slope faster so that there is little to no overlap between clearly different KE of rounds. Additionally weapons with big damage using lots of dice will cluster statistically towards an average. Wildly high and low results become very rare. A side benefit is that you can have the room to express intermediate cartridges/different technologies/special rounds/ without running roughshod over the data point values or making each round very similar to the next. You rejected the argument on the grounds that it moves too far away from the values adopted from CoC for BRP.

And that is one of the big problems, Unless we want to throw out everything else and rewrite the combat rules, we are never going to get values that work right for everything. Even with a rewrite there would still be problems. There isn't one RPG that models modern ballistics perfectly. It's all very complex.

I agree that it is complex. I do not agree that we can’t pare down the inconsistencies that currently exist and keep it fairly transparent.As for rewriting the combat rules I think that it is time to seriously consider it. The firearm combat rules are a legacy of CoC. They may work very well for some people but it may be time to make a break with it and create rules that can capture the flavor of other genres better than CoC can. While such a thing is too late for BRP it might be doable for a supplement or a revision. I know, I know it sounds like sacrilage but I know that there are two kinds of gamers out there: those that care about such things and those that don’t. If the revisions cause minimal disruption to the play of those that don’t care why shouldn’t the rules evolve to serve both kinds of gamers?

Do we want to do up weapon damage drop off by range?

More than likely.

If so do we want to be accurate and model how some weapons drop off slower than others?

Perhaps. That information needs to be able to be presented on the character sheet in an intuitive format.

Do we want to get rid of the random die roll against armor so a firearm will consistently penetrate armor?

I want consistent pentration no matter how it is achieved. I advocate a two-step process. APs should be matched or overcome by penetration which is dependant on the velocity, mass, and construction of the round itself. Die rolls should reduce the HP of an object. I can see giving the armor a die roll once the fire is arriving at an oblique as an aid against penetration.

Do we want to separate penetration form damage?

Yes. See above.

Do we want to make sure that penetration still plays a factor since it is a major factor in the latter?

For instance if we sett the 7.62 to, say Penetration 1D3+9, and then divided the total by 10 and multiplied it by 2D6 we would probably get a more accurate result, but it would be a pain to play.

Yes that would be a pain but it isn’t the only way to model it. Can you explain how you derived that formula or were you just looking for something horrendous to present? How about a system where penetration is matched to AP and excess pentration become bonus dice of damage or a straight damage add. Douglas Cole has presented an idea for expressing armor as dice of damage that is soaked up from the weapon’s pool of damage dice. I need to find it again.

Going back to your source and the concrete tests, that is another problem with weapons. Each weapon affects each material differently. So by your source a 7.62 is better at concrete that a .50 cal.

That is not what I wrote. How did you get that idea? :confused:

But what about clay? Or brick?

For instace just looking at the .50 cal. data from Gary's:

Range

Homogeneous Plate

Face Hardened Plate

Sand

Clay

Concrete

200m

25.4mm

22.9mm

355.6mm

711.2mm

50.8mm

600m

17.6mm

12.7mm

304.8mm

685.8mm

25.4mm

1500m

7.6mm

5.1mm

152.4mm

533.4mm

25.4mm

Now look at the drop off in penetration. For plate the penetration value at 1500m is about 30% of the value at 200m, for Hardened Plate 45%, Sand 43%, Clay 75%, and Concrete 50%. So, if this was done up for a game, each material would have to stop a different amount of APs at each range.

Hogwash. The change in penetration is a function of the change in velocity at that range. All of the targets are struck at the same velocity at a particular range within the limits of manufacturing etc. The same energy is delivered to each target but each target handles it differently. The material sucks up penetration to overcome the material’s APs. Then damage is applied to the HPs of the object. Doing it the way you outline is more of a pain than supplying drop-off data for the weapons and counter-intuitive to boot. I mean really the concrete gets more fragile as we get farther away from it? Get far enough away and it will collapse on it's own!

Any sort of universal chart won't work.

IF we set if for one material and range it wont work for the others. For instance, I we set the damages so that a .50 cal will punch though 7.6mm of plate, and 25,4 mm of concrete at 1500 yards, then if we adjust that damage up for the bullet to penetrate 17.6mm of plate at 600m, and 25.4mm at 200m, the increase in penetration will carry over to the concrete and will end up going though 58.8mm and 84.9mm of concrete at the respective ranges.

You are right they don’t work. Let’s move on to something else. APs and HP per unit of material allows you to show the differences in the materials which is the important thing when dealing with breaking and penetrating materials.

So this is close, at least for these two data points. Good call on the sand. Sand sucks to shoot through by all accounts.

Uhmmm…the sandbag doesn’t have more HPs than 2” of steel. 1” of steel is 19 and the large sandbag has 20, at least in CoC 5th Ed. Did your finger slip?

Sand is better only when you don’t have to transport it. Besides plate’s APs don’t leak out when you do put a hole in it!

And that is a problem because 9s can’t really do that can they?

Sorry this reply took so long, I had some other things to attend to.

Joseph Paul

However, for what it's worth, in the real world a 7.62 isn't going to get though 6 inches of cement, but a .50 cal will do so.

It doesn't look like the Army agrees with that. Penetration of concrete with M2 ball ammo is 2" at 200 meters. There appears to be a table giving the following in a FM- At 25 deg oblique and 100 m it takes 300 rounds to breach a 24" thick reinforced concrete wall and at 200 m it takes 1200. What is rebar reinforcement worth?

SLAP ammo appears to do about a third better in armor than M2 AP(I am presuming homogenous plate) so it may do about 3" of concrete but I don't have a source for that.

1" of concrete= Ln25.4*5.77-11? So 7.66 round up(?) to 8? .50 I am told will do 4d6+3 so 17 on avg. 2" of concrete should be about 12 AP so the .50 will still penetrate. The 7.62 does 2d6+3 (?) avg 10 pts. Hmm consulting my sources shows that the army believes that 7.62 mm *will* do 2" of concrete. How odd, I wouldn't have thought so. So this is close, at least for these two data points. Good call on the sand. Sand sucks to shoot through by all accounts.

Joseph Paul

FTL:2448- Neat ideas and some great systems buggered up by too many ways to run the combat and level based advancement.

To answer the OPs question: This doesn't affect me one whit. I never liked GW's stuff and stopped getting White Dwarf the moment it became a house organ. My condolences to those that feel this more keenly than I.

What this does do is remind me of how often I have been affected by Chaosium cancelling projects or not supporting games. Ringworld, Elfquest, Questworld and Superworld all got published and then languished with very little support. Eventually the licensed material got tied up or ended. This raises the question for me as to what Chaosium has learned about making a line profitable enough to keep. Anyone have any thoughts on what it takes either in general or specifically for Chaosium?

Chaosium has a line of fiction that they were making money on. Anybody know if that is going to affect how it devotes itself to supporting our RPG hobby?

And yes I thought it germane to connect the Dark Heresy travesty to Chaosium’s track record because this is after all BRPCentral even if this is the Gamers Cavern Forum. If that is too wildly inappropriate we can move the question elsewhere.

Journey to the West

Are the works of Jules Verne and H.G. Wells in the Public Domain now?

Captain Nemo and MArtian Invasions never go out of style.

One way to find out is to peruse the Project Gutenberg list.

It scans and makes e-books in vanilla text of works in the public domain. if it is in Gutenberg it is copyright free in the US.

it looks like much of Edgar Rice Burrough's stuff is there.

Well of course the monkeys!

Oh the Irony.

Seriously though, I hope it is pretty obvious I was joking there. I'd never say anything mean for real. :innocent:

Reading it cold, no you can't tell that you were joking. Really.

Joseph Paul

No joke to spoil. I just liked my comparison and thought I gave a good reason to choose the .45 over the .22. even if I misunderstood your actual comment.

And while I don't know SD personally, you never know.

Rod Leary

Oh! I get the the reasons you listed, thank you for them.

Sent you a private message with an email addy in it.

Thanks again

I would most certainly like to see your efforts. if you could E-mail them to the addy in my profile please?

Sorry Joseph, for some reason I thought the point was that no one would want a .45 as the .22 did more damage over the course of a round. But damn it, I still made a good point.

Rod Leary

OK I am confused and not getting the reason for the big smiley. At the risk of spoilng the joke could you please explain it? Also are you related to SD, I noticed the 'Leary' on the end of both your names.