Back to the main page

Mailing List Logs for ShadowRN

Message no. 1
From: Marc Renouf renouf@********.com
Subject: Armor Penetration
Date: Fri, 26 Feb 1999 12:08:46 -0500 (EST)
On Fri, 26 Feb 1999, Sven De Herdt wrote:

> 2. I think it is crap that you have to compare the UNMODIFIED power of
> a weapon with the armor rating. This means that a HMG won't penetrate
> the armor, but a sniper would? This sounded a bit illogical to me,
> especially if you consider the caliber of the HMG or am I mistaken in
> this one?

Well, one of the things to consider is not just the caliber but
also the amount of powder behind the round and the penetration dynamics of
the bullet. For instance, the AK-47 uses a 7.62x39mm round. By SR
standards, that's 8M. The M60 also uses a 7.62mm round, but it's a
7.62x54 (though it may be x51, I can't remember), and thus has got a hell
of a lot more powder behind it, and that brings it up to MMG status (8S I
think).
Further, even if you're firing the same bullet, the barrel length
makes a difference. The longer the barrel, the more time the expanding
gasses have to accelerate the bullet, the faster your overall muzzle
velocity is going to be. Thus, a Dragunov SVD (which *also* fires a
7.62x54mm round) gets the 14S given to a sniper rifle simply because the
barrel is so freaking long. Its muzzle velocity is over 2750 fps, which
is about double what most pistol rounds travel at.
Higher muzzle velocities mean more range and more punch at any
given range, so it's much more complicated than just comparing
bullet calibers.

Marc
Message no. 2
From: Adam Getchell acgetchell@*******.edu
Subject: Armor Penetration
Date: Fri, 26 Feb 1999 10:36:29 -0800
When considering the damage potential of a weapon, there are three main
criteria:

Kinetic energy, as it relates to the amount of joules the weapon can
deliver to the target. This relates directly to tissue damage.

Momentum, which provides knockdown capability but, more importantly,
preserves kinetic energy through the trajectory of the round.

And physical characteristics of the bullet; ie diameter, elasticity,
aerodynamics (both in-flight and within the target). This affects both
energy retention in flight and energy delivery to the target in terms of
wound channel and tissue damage.

Dr. Martin Fackler of the Wound Ballistics Lab in Maryland has published
that "damage" is primarily a function of kinetic energy. Also, "hydrostatic
shock" does not add significantly to trauma caused by round impact, with
the sole exception of rigidly contained areas of the body (ie the skull).

Finally, as far as the question of barrel length, note that there is an
optimal length for each round wherein the gunpowder deflagration imparts
maximum energy. Shorter barrels lose some of this energy transfer, while
longer barrels reduce the total energy with friction. An edition of Guns
and Ammo ran several tests with various length barrels and a ballistics
setup to demonstrate this point.

As such, Shadowrun miserably fails to tie in these factors in any sort of
meaningful way. For example, let's put the standard rifle in the .303 class
of weapon. There are two damage levels, 7S and 10S, which we'll assume
relate to barrel length (carbine and rifle respectively).

Now lets take the Barret sniper rifle, .50 caliber weapon, 14D. We may
attest that the increase is due to higher velocity, heavier round, and a
longer barrel. However (and I don't have any ballistics tables on me), I'm
not sure that the velocity difference between a .303 and .50 is large (by
which I mean it is within a factor of 2), but we'll leave that open.

Now let's compare a Heavy Machine gun, which by rights would be a .50
caliber /14.2mm weapon also, and does 10S.

Compared with a Barrett, an M2 .50 HMG lacks only barrel length and
possibly, improved bullet composition. As I noted above, though, barrel
length factors are at most 10-20% of kinetic energy. The jump from 10S to
14D is puzzling in that light, unless we postulate the existance of
ammunition that is able to increase power by +4 and wound level by 1.

Perhaps that is how one could model the .224 BOZ pistol round, which is
capable of penetrating armor panels in the Bradley AFV and the next
generation of body armor, but I would not like to see such escalation.

When I proposed the OICW Block 4, I was extremely conservative in the
effects of ETC propellant. Imagine an assault rifle firing rounds at 2000
meters per second or so. Using the examples that have been given to us in
FOF and elsewhere, how would one model a doubling of kinetic energy?

Perhaps someone with access to ballistics tables will add comments?
--Adam

acgetchell@*******.edu
"Invincibility is in oneself, vulnerability in the opponent." --Sun Tzu
Message no. 3
From: Ereskanti@***.com Ereskanti@***.com
Subject: Armor Penetration
Date: Fri, 26 Feb 1999 17:26:47 EST
I am going to admit to this right now. I don't know much about firepower
configurations, but after reading Adam's post, a small set of brainstorms hit
me. As such, I'm just adding a few things to a few of his paragraphs. Let's
see if this helps.


In a message dated 2/26/1999 1:39:38 PM US Eastern Standard Time,
acgetchell@*******.edu writes:

>
> Kinetic energy, as it relates to the amount of joules the weapon can
> deliver to the target. This relates directly to tissue damage.

this would be "Power" of the weapon. The "9" in 9M

> Momentum, which provides knockdown capability but, more importantly,
> preserves kinetic energy through the trajectory of the round.

To me, for SR's mechanics, this would be "Range."

> And physical characteristics of the bullet; ie diameter, elasticity,
> aerodynamics (both in-flight and within the target). This affects both
> energy retention in flight and energy delivery to the target in terms of
> wound channel and tissue damage.


And finally, this would be Damage Level. The "M" in 9M.

-K
Message no. 4
From: Paul J. Adam Paul@********.demon.co.uk
Subject: Armor Penetration
Date: Fri, 26 Feb 1999 22:56:03 +0000
In article <v04011709b2fc93f6a209@[128.120.118.25]>, Adam Getchell
<acgetchell@*******.edu> writes
>When considering the damage potential of a weapon, there are three main
>criteria:
>
>Kinetic energy, as it relates to the amount of joules the weapon can
>deliver to the target. This relates directly to tissue damage.

To an extent, but not quite "directly". As Dr Fackler says, when a
meteorite comes through your roof, you don't care how much "energy it
transferred", you care how big a hole it made.

>Momentum, which provides knockdown capability but, more importantly,
>preserves kinetic energy through the trajectory of the round.
>
>And physical characteristics of the bullet; ie diameter, elasticity,
>aerodynamics (both in-flight and within the target). This affects both
>energy retention in flight and energy delivery to the target in terms of
>wound channel and tissue damage.

>
>Dr. Martin Fackler of the Wound Ballistics Lab in Maryland has published
>that "damage" is primarily a function of kinetic energy.

To an extent. More precisely, that a round needs both adequate kinetic
energy and a means to convert that into damaged body tissue.

>Also, "hydrostatic
>shock" does not add significantly to trauma caused by round impact, with
>the sole exception of rigidly contained areas of the body (ie the skull).

Or the liver, or fluid-filled organs such as the stomach after a meal...
but Fackler's scathing about the idolatry of "hydrostatic shock" and
"temporary cavity" as wounding mechanisms.


>Finally, as far as the question of barrel length, note that there is an
>optimal length for each round wherein the gunpowder deflagration imparts
>maximum energy. Shorter barrels lose some of this energy transfer, while
>longer barrels reduce the total energy with friction. An edition of Guns
>and Ammo ran several tests with various length barrels and a ballistics
>setup to demonstrate this point.

I recall this. I also recall comments about how, due to internal
ballisic considerations, a 3"-barreled 9mm Parabellum revolver could
achieve more hitting power than an almost identical weapon chambered for
.357 Magnum. While if you double the barrel the Magnum has the
advantage, that's not an option for most backup pieces.


>As such, Shadowrun miserably fails to tie in these factors in any sort of
>meaningful way. For example, let's put the standard rifle in the .303 class
>of weapon. There are two damage levels, 7S and 10S, which we'll assume
>relate to barrel length (carbine and rifle respectively).

I figured it was two different calibres, myself; say, .308 and .338, or
something similar.

But then, FASA never made much sense on the issue. If the AK-97 even
vaguely resembles the AK-74, then the AK-97 Carbine equates to the AKSU
of today; and that weapon is both more lethal and more penetrative than
any 9mm/.40cal SMG of today. Yet it's _less_ lethal than Shadowrun SMGs?


The SR2 firearms damage rules were playable, especially as they related
to shotguns / assault rifles / pistols. They weren't _realistic_, but
then being told "They've got automatic weapons and they outnumber you
five to one. You've got a 9mm pistol. You die. I can't be bothered
rolling dice when it's so obvious what will happen." isn't fun to play.

>Now lets take the Barret sniper rifle, .50 caliber weapon, 14D.

From "Elven Fire", the "sniper rifle" is a .655 subsonic, which makes
more sense in some ways for such a high damage code (though offhand I'd
make it 10D myself, and have HMGs at 15S base damage)

>We may
>attest that the increase is due to higher velocity, heavier round, and a
>longer barrel. However (and I don't have any ballistics tables on me), I'm
>not sure that the velocity difference between a .303 and .50 is large (by
>which I mean it is within a factor of 2), but we'll leave that open.

Assuming you mean .303 Lee-Enfield, then the "standard" ballistic table
entry is for a 180-grain bullet at 2460 feet per second.

.50 Browning Machine Gun is about 670 grains of bullet, at 2910 feet per
second.

>Compared with a Barrett, an M2 .50 HMG lacks only barrel length and
>possibly, improved bullet composition.

Why? If it feeds in a Barrett, it'll feed in a M2HB heavy machine gun.
Indeed, the favoured real-world load for the Barrett rifles - the
Raufoss multipurpose - was designed for and is widely used in the HMG,
and was later adopted for the rifles.

>When I proposed the OICW Block 4, I was extremely conservative in the
>effects of ETC propellant. Imagine an assault rifle firing rounds at 2000
>meters per second or so. Using the examples that have been given to us in
>FOF and elsewhere, how would one model a doubling of kinetic energy?

16M damage from an assault weapon, perhaps?

--
Paul J. Adam
Message no. 5
From: Gurth gurth@******.nl
Subject: Armor Penetration
Date: Sat, 27 Feb 1999 12:11:01 +0100
According to Ereskanti@***.com, at 17:26 on 26 Feb 99, the word on
the street was...

> > Momentum, which provides knockdown capability but, more importantly,
> > preserves kinetic energy through the trajectory of the round.
>
> To me, for SR's mechanics, this would be "Range."

It's something not represented in SR mechanics, I think. A bullet loses
momentum the further down-range it gets, which could be included in SR by
lowering either the Power Level or the Knock-Down TN for each range beyond
Short (-1 per range category would be a way to do this).

The actual range is determined mainly by the bullet's velocity and
aerodynamics. The faster you shoot something away horizontally, the
further it will get before it hits the ground (this, BTW, is elementary
physics). Aerodynamics comes into this because it can provide lift to the
bullet (a bullet fired in a horizontal line will actually rise above that
line for a while) and keep the bullet from losing velocity, thus making it
go farther.

> > And physical characteristics of the bullet; ie diameter, elasticity,
> > aerodynamics (both in-flight and within the target). This affects both
> > energy retention in flight and energy delivery to the target in terms of
> > wound channel and tissue damage.
>
> And finally, this would be Damage Level. The "M" in 9M.

Most likely, yes. However, I'd say it's also partly in the Power Level --
PL is, IMHO, part potential armor penetration and part wound-causing
capabilities of a weapon.

--
Gurth@******.nl - http://www.xs4all.nl/~gurth/index.html
"The only mechanoids ever issued with genetalia were those serving
aboard Italian starships" --Kryten, Red Dwarf VIII
-> NERPS Project Leader * ShadowRN GridSec * Unofficial Shadowrun Guru <-
->The Plastic Warriors Page: http://shadowrun.html.com/plasticwarriors/<-
-> The New Character Mortuary: http://www.electricferret.com/mortuary/ <-

GC3.1: GAT/! d-(dpu) s:- !a>? C+(++)@ U P L E? W(++) N o? K- w+ O V? PS+
PE Y PGP- t(+) 5++ X++ R+++>$ tv+(++) b++@ DI? D+ G(++) e h! !r(---) y?
Incubated into the First Church of the Sqooshy Ball, 21-05-1998
Message no. 6
From: Gurth gurth@******.nl
Subject: Armor Penetration
Date: Sat, 27 Feb 1999 12:11:02 +0100
According to Marc Renouf, at 12:08 on 26 Feb 99, the word on
the street was...

> Well, one of the things to consider is not just the caliber but
> also the amount of powder behind the round and the penetration dynamics of
> the bullet. For instance, the AK-47 uses a 7.62x39mm round. By SR
> standards, that's 8M. The M60 also uses a 7.62mm round, but it's a
> 7.62x54 (though it may be x51, I can't remember)

It's 7.62x51, which is the rimless NATO-standard full-size round that
pretended to be an assault rifle caliber. 7.62x54 is the rimmed Russian
ammo from the late 19th century, used in such weapons as the Mosin-Nagant
1891 infantry rifle, SVD sniper rifle, PK machinegun, etc.

> Higher muzzle velocities mean more range and more punch at any
> given range, so it's much more complicated than just comparing
> bullet calibers.

Then add in what a bullet is made of, its shape, and lots of other
factors...

--
Gurth@******.nl - http://www.xs4all.nl/~gurth/index.html
"The only mechanoids ever issued with genetalia were those serving
aboard Italian starships" --Kryten, Red Dwarf VIII
-> NERPS Project Leader * ShadowRN GridSec * Unofficial Shadowrun Guru <-
->The Plastic Warriors Page: http://shadowrun.html.com/plasticwarriors/<-
-> The New Character Mortuary: http://www.electricferret.com/mortuary/ <-

GC3.1: GAT/! d-(dpu) s:- !a>? C+(++)@ U P L E? W(++) N o? K- w+ O V? PS+
PE Y PGP- t(+) 5++ X++ R+++>$ tv+(++) b++@ DI? D+ G(++) e h! !r(---) y?
Incubated into the First Church of the Sqooshy Ball, 21-05-1998
Message no. 7
From: David Hinkley dhinkley@***.org
Subject: Armor Penetration
Date: Sat, 27 Feb 1999 03:27:43 -0800
Date sent: Fri, 26 Feb 1999 12:08:46 -0500 (EST)
From: Marc Renouf <renouf@********.com>
To: "'shadowrn@*********.org'" <shadowrn@*********.org>
Subject: Armor Penetration
Send reply to: shadowrn@*********.org

>
>
> On Fri, 26 Feb 1999, Sven De Herdt wrote:
>
> > 2. I think it is crap that you have to compare the UNMODIFIED power of
> > a weapon with the armor rating. This means that a HMG won't penetrate
> > the armor, but a sniper would? This sounded a bit illogical to me,
> > especially if you consider the caliber of the HMG or am I mistaken in
> > this one?
>
> Well, one of the things to consider is not just the caliber but
> also the amount of powder behind the round and the penetration dynamics of
> the bullet. For instance, the AK-47 uses a 7.62x39mm round. By SR
> standards, that's 8M. The M60 also uses a 7.62mm round, but it's a
> 7.62x54 (though it may be x51, I can't remember), and thus has got a hell
> of a lot more powder behind it, and that brings it up to MMG status (8S I
> think).

7.62 Nato is the x51, World War II Soviet (and Soviet MMG) is 7.62x54, and
the AK is 7.62x39





David Hinkley
dhinkley@***.org

===================================================Those who are too intelligent to engage
in politics
are punished by being governed by those who are not
--Plato
Message no. 8
From: David Hinkley dhinkley@***.org
Subject: Armor Penetration
Date: Sat, 27 Feb 1999 03:27:43 -0800
Date sent: Fri, 26 Feb 1999 10:36:29 -0800
To: shadowrn@*********.org
From: Adam Getchell <acgetchell@*******.edu>
Subject: Re: Armor Penetration
Send reply to: shadowrn@*********.org

[SNIP]
>
> Now lets take the Barret sniper rifle, .50 caliber weapon, 14D. We may
> attest that the increase is due to higher velocity, heavier round, and a
> longer barrel. However (and I don't have any ballistics tables on me), I'm
> not sure that the velocity difference between a .303 and .50 is large (by
> which I mean it is within a factor of 2), but we'll leave that open.
>
> Now let's compare a Heavy Machine gun, which by rights would be a .50
> caliber /14.2mm weapon also, and does 10S.
>
> Compared with a Barrett, an M2 .50 HMG lacks only barrel length and
> possibly, improved bullet composition. As I noted above, though, barrel
> length factors are at most 10-20% of kinetic energy. The jump from 10S to
> 14D is puzzling in that light, unless we postulate the existance of
> ammunition that is able to increase power by +4 and wound level by 1.

I do not believe that the difference in barrel length between a Barrett and a
M2HB is enough to have a significant effect on the weapons performance.
As to the jump, given the lack of correspondence with real life weapons
performance found in thie rest of the firearms tables why would you expect it
here?






David Hinkley
dhinkley@***.org

===================================================Those who are too intelligent to engage
in politics
are punished by being governed by those who are not
--Plato
Message no. 9
From: Ereskanti@***.com Ereskanti@***.com
Subject: Armor Penetration
Date: Sun, 28 Feb 1999 10:05:23 EST
In a message dated 2/27/1999 6:12:36 AM US Eastern Standard Time,
gurth@******.nl writes:

> > > Momentum, which provides knockdown capability but, more importantly,
> > > preserves kinetic energy through the trajectory of the round.
> >
> > To me, for SR's mechanics, this would be "Range."
>
> It's something not represented in SR mechanics, I think. A bullet loses
> momentum the further down-range it gets, which could be included in SR by
> lowering either the Power Level or the Knock-Down TN for each range beyond
> Short (-1 per range category would be a way to do this).

Then perhaps Gurth, as SR is more abstract in these advanced concepts (Knock-
Down/Kickback), this is what would happen at longer ranges?

-K
Message no. 10
From: Gurth gurth@******.nl
Subject: Armor Penetration
Date: Sun, 28 Feb 1999 19:50:49 +0100
According to Ereskanti@***.com, at 10:05 on 28 Feb 99, the word on
the street was...

> > It's something not represented in SR mechanics, I think. A bullet loses
> > momentum the further down-range it gets, which could be included in SR by
> > lowering either the Power Level or the Knock-Down TN for each range beyond
> > Short (-1 per range category would be a way to do this).
>
> Then perhaps Gurth, as SR is more abstract in these advanced concepts (Knock-
> Down/Kickback), this is what would happen at longer ranges?

I don't quite understand what you're referring to with the word "this,"
here. If you mean the Power Level or Knockback TN should be lowered at
range, I'd most likely agree with you, although adding it to SR does make
the game more complex than many people would like. (Note that I don't
intend to play with a rule like this myself; if I want a realistic combat
simulation I'll use Phoenix Command rules :)

--
Gurth@******.nl - http://www.xs4all.nl/~gurth/index.html
"The only mechanoids ever issued with genetalia were those serving
aboard Italian starships" --Kryten, Red Dwarf VIII
-> NERPS Project Leader * ShadowRN GridSec * Unofficial Shadowrun Guru <-
->The Plastic Warriors Page: http://shadowrun.html.com/plasticwarriors/<-
-> The New Character Mortuary: http://www.electricferret.com/mortuary/ <-

GC3.1: GAT/! d-(dpu) s:- !a>? C+(++)@ U P L E? W(++) N o? K- w+ O V? PS+
PE Y PGP- t(+) 5++ X++ R+++>$ tv+(++) b++@ DI? D+ G(++) e h! !r(---) y?
Incubated into the First Church of the Sqooshy Ball, 21-05-1998
Message no. 11
From: Marc Renouf renouf@********.com
Subject: Armor Penetration
Date: Mon, 1 Mar 1999 09:30:41 -0500 (EST)
On Sat, 27 Feb 1999, Gurth wrote:

> > The M60 also uses a 7.62mm round, but it's a 7.62x54 (though it may
> > be x51, I can't remember)
>
> It's 7.62x51, which is the rimless NATO-standard full-size round that
> pretended to be an assault rifle caliber. 7.62x54 is the rimmed Russian
> ammo from the late 19th century, used in such weapons as the Mosin-Nagant
> 1891 infantry rifle, SVD sniper rifle, PK machinegun, etc.

Yeah, I was unaware that 7.62x54 were rimmed until this weekend,
when I put 60 of them through my brand new SVD. Damn! That's a fine
weapon! I wish I'd had time to really put it through its paces at
extended ranges, but alas, I did not.

Marc
Message no. 12
From: Twist0059@***.com Twist0059@***.com
Subject: Armor Penetration
Date: Mon, 1 Mar 1999 09:41:12 EST
One thing that always bothered me about the armor penetration rules is
that they only count for reductions in armor values, not what the round does
to the clothing.

For instance, a Predator round fired at a samurai wearing an Armor Jacket
will probably not penetrate, but can the samurai realistically now wear that
jacket in public, with a slug compacted and lodged in a plate under the now-
ragged fabric?

Considering that a samurai could continue to logically shrug off many such
attacks without penetration, wouldn't the Armor Jacket eventually be so
obvious as to not just be worthless, but also a serious attention-grabbed for
any sort of local police force?




Twist
Message no. 13
From: Damian Robinson max.robinson@**.net.au
Subject: Armor Penetration
Date: Thu, 04 Mar 1999 18:18:34 +1100
Paul J. Adam wrote:
>
> In article <v04011709b2fc93f6a209@[128.120.118.25]>, Adam Getchell
> <acgetchell@*******.edu> writes
> >When considering the damage potential of a weapon, there are three main
> >criteria:
> >
> >Kinetic energy, as it relates to the amount of joules the weapon can
> >deliver to the target. This relates directly to tissue damage.
>
> To an extent, but not quite "directly". As Dr Fackler says, when a
> meteorite comes through your roof, you don't care how much "energy it
> transferred", you care how big a hole it made.

PLEASE, don't get Fackler involved in this, or the M&S One Shot Stop
people will come out! I get enough of this in Glock-l!!!
This is a flame war waiting to happen!
GRIDSEC!
GRIDSEC!
Help me out here!
they're going to burn us all!
;-{>

<snip hydrostatic shock and momentum bits>

> >Finally, as far as the question of barrel length, note that there is an
> >optimal length for each round wherein the gunpowder deflagration imparts
> >maximum energy. Shorter barrels lose some of this energy transfer, while
> >longer barrels reduce the total energy with friction. An edition of Guns
> >and Ammo ran several tests with various length barrels and a ballistics
> >setup to demonstrate this point.
>
> I recall this. I also recall comments about how, due to internal
> ballisic considerations, a 3"-barreled 9mm Parabellum revolver could
> achieve more hitting power than an almost identical weapon chambered for
> .357 Magnum. While if you double the barrel the Magnum has the
> advantage, that's not an option for most backup pieces.

The Amount of difference in power between most 9 mm cal (9 mm, .38,
.357) rounds really is minuscule when you look at it, especially when
you compare to any rifle rounds.
Its not until you start getting up to .44 Magnum and 10 mm that there
is really a difference. Also the Lethality of a given round cannot
truly be compared to any other round. Ballistic Gelatin gives us a
basis for some comparison, but there is no way to convert that into
what will happen in the human body.

> >As such, Shadowrun miserably fails to tie in these factors in any sort of
> >meaningful way. For example, let's put the standard rifle in the .303 class
> >of weapon. There are two damage levels, 7S and 10S, which we'll assume
> >relate to barrel length (carbine and rifle respectively).
>
> I figured it was two different calibres, myself; say, .308 and .338, or
> something similar.

Perhaps .308 & 30.06?
But you loose about 25 Fps per inch of barrel IIRC, when you shorten
it.

> But then, FASA never made much sense on the issue. If the AK-97 even
> vaguely resembles the AK-74, then the AK-97 Carbine equates to the AKSU
> of today; and that weapon is both more lethal and more penetrative than
> any 9mm/.40cal SMG of today. Yet it's _less_ lethal than Shadowrun SMGs?

Its a glitch...
or
Perhaps the Carbine version is in 9 mm Makarov?
:-{>

> The SR2 firearms damage rules were playable, especially as they related
> to shotguns / assault rifles / pistols. They weren't _realistic_, but
> then being told "They've got automatic weapons and they outnumber you
> five to one. You've got a 9mm pistol. You die. I can't be bothered
> rolling dice when it's so obvious what will happen." isn't fun to play.

this is a roleplaying game, and who brought realism into this?
;-{>

Just look at the weapon ranges!
or the FA rules!
Or grenades!

> >Now lets take the Barret sniper rifle, .50 caliber weapon, 14D.

I looked at the Barret, and compared it to the assault cannon. I'm
assuming that the assault cannon is .50 BMG or some derivative
thereof, and the Barret 121 is a .338 Lapua or similar. They have
similar effects on people, but one is better Vs Vehicles than the
other.

> >From "Elven Fire", the "sniper rifle" is a .655 subsonic,
which makes
> more sense in some ways for such a high damage code (though offhand I'd
> make it 10D myself, and have HMGs at 15S base damage)

It makes more sense to assume that the sniper rifle and HMG use
different rounds, as I mentioned above. The .338 Lapua is more
inherently accurate than .50 BMG. I also take anything out of the SR
fiction as merely filler, rather than a canon (Cannon? ;-{>) source).

> >We may
> >attest that the increase is due to higher velocity, heavier round, and a
> >longer barrel. However (and I don't have any ballistics tables on me), I'm
> >not sure that the velocity difference between a .303 and .50 is large (by
> >which I mean it is within a factor of 2), but we'll leave that open.
>
> Assuming you mean .303 Lee-Enfield, then the "standard" ballistic table
> entry is for a 180-grain bullet at 2460 feet per second.
>
> .50 Browning Machine Gun is about 670 grains of bullet, at 2910 feet per
> second.

that sounds about right.
over 3 times the mass, at 25% faster velocity.
Probably closer to 4 times the energy.

<snip>

>
> >When I proposed the OICW Block 4, I was extremely conservative in the
> >effects of ETC propellant. Imagine an assault rifle firing rounds at 2000
> >meters per second or so. Using the examples that have been given to us in
> >FOF and elsewhere, how would one model a doubling of kinetic energy?
>
> 16M damage from an assault weapon, perhaps?

Bright red smear as the round melts or disintigrates?

If anyone is interested, I've got some stats on RL ammo, and what it
should be (IMNSHO). Drop me a line, or If I get enough people
interested, I'll post them to the list. It includes my opinion on the
.224 BOZ and the FN 5.7 round too...

> --
> Paul J. Adam

Oh, and Paul, just a quick Q, did you ever do up game stats for all
those 2057 RN ships you wrote up once?

Just curious.

--
Cheers
Damian

Home Page:
http://www.geocities.com/Area51/Dreamworld/4808/
pay a visit, and please don't forget the Guestbook...

ICQ?
#14030875
Message no. 14
From: Paul J. Adam Paul@********.demon.co.uk
Subject: Armor Penetration
Date: Fri, 5 Mar 1999 23:00:43 +0000
In article <36DE33C9.3CB5EEDE@**.net.au>, Damian Robinson
<max.robinson@**.net.au> writes
>Paul J. Adam wrote:
>> To an extent, but not quite "directly". As Dr Fackler says, when a
>> meteorite comes through your roof, you don't care how much "energy it
>> transferred", you care how big a hole it made.
>
>PLEASE, don't get Fackler involved in this, or the M&S One Shot Stop
>people will come out! I get enough of this in Glock-l!!!
>This is a flame war waiting to happen!

Okay. I'll say I'm a Facklerite and leave it at that :)

>> I recall this. I also recall comments about how, due to internal
>> ballisic considerations, a 3"-barreled 9mm Parabellum revolver could
>> achieve more hitting power than an almost identical weapon chambered for
>> .357 Magnum. While if you double the barrel the Magnum has the
>> advantage, that's not an option for most backup pieces.
>
>The Amount of difference in power between most 9 mm cal (9 mm, .38,
>.357) rounds really is minuscule when you look at it, especially when
>you compare to any rifle rounds.

Yep. Shot placement ends up mattering far more than notional differences
in ballistics. Better to hit with a .22 than miss with a .44... and just
hitting the target is a damn sight harder than many realise.

>Its not until you start getting up to .44 Magnum and 10 mm that there
>is really a difference.

IMHO, one of the better handguns around for those able to make good use
of it - the Glock 20. Fifteen rounds of 10mm in a nice, handy package...

I preferred .45ACP, but then I only ever shot at cardboard and it was a
lot easier to get fixings to handload .45. (KTW sold 200-grain .45 LSWs
for UKP3 for 250, if you wanted 10mm you bought factory ammo, bought
jacketed bullets, or cast your own. Here in the UK at least.)

>Also the Lethality of a given round cannot
>truly be compared to any other round. Ballistic Gelatin gives us a
>basis for some comparison, but there is no way to convert that into
>what will happen in the human body.

And in reality, luck plays a huge part.



>> I figured it was two different calibres, myself; say, .308 and .338, or
>> something similar.
>
>Perhaps .308 & 30.06?

Could easily be. I'm less and less convinced about trying to place
calibres precisely within Shadowrun's damage system: if only because too
many people all disagree, for contradictory but often still good reasons
:) To each his own...

>But you loose about 25 Fps per inch of barrel IIRC, when you shorten
>it.

Depends from where you start shortening it. For instance, the M4 carbine
seems to give up very little in real-world performance to the M16 rifle:
shortening the barrel doesn't seem to cripple its accuracy or hitting
power. On the other hand, I doubt you could knock much off the barrels
of the L1A1 SLRs I used to use without noticeably affecting accuracy and
muzzle velocity.

For any cartridge (and it's sensitive even to the powder load, let alone
bullet calibre and weight) there's an optimum barrel length. Longer
isn't always better. (If nothing else, longer is more susceptible to
bending, warping, whip or thermal distortion...)


>> But then, FASA never made much sense on the issue. If the AK-97 even
>> vaguely resembles the AK-74, then the AK-97 Carbine equates to the AKSU
>> of today; and that weapon is both more lethal and more penetrative than
>> any 9mm/.40cal SMG of today. Yet it's _less_ lethal than Shadowrun SMGs?
>
>Its a glitch...
>or
>Perhaps the Carbine version is in 9 mm Makarov?
>:-{>

Nope, the new Russian 9mm is _scary_. Take a 7.62mm x 39 and neck it out
for a 9mm heavy (~300 grain) bullet and fire it at just-subsonic
velocity for easy suppression. Now _that_ is a submachinegun.

Hell, their 9mm Gyurza pistol round will shoot through two Threat Level
III armour vests, front-back-front-back at 50 metres. Their Bad Guys
wear lots of armour, the Russians are developing weapons to cope.


>> The SR2 firearms damage rules were playable, especially as they related
>> to shotguns / assault rifles / pistols. They weren't _realistic_, but
>> then being told "They've got automatic weapons and they outnumber you
>> five to one. You've got a 9mm pistol. You die. I can't be bothered
>> rolling dice when it's so obvious what will happen." isn't fun to play.
>
>this is a roleplaying game, and who brought realism into this?
>;-{>

I like _some_ realism, but I also like the game to be playable.
Realistically, firefights get you killed, fast.

>Just look at the weapon ranges!

No, thanks.

>or the FA rules!

Worse.

>Or grenades!

I've seen worse grenade rules in roleplaying games. SR isn't _too_
bad... at least grenades can hurt you big-time in confined spaces or at
close range.

I saw some stats for a comparison of the US M26 and the German DM51
grenade, and the consensus was that past 5 metres range neither were
particularly lethal: the M26's fragments were too few and too likely to
miss, the DM51's smaller fragments had lost too much energy and wouldn't
inflict disabling wounds. Grenades are nasty, but shouldn't be
overrated.

>I looked at the Barret, and compared it to the assault cannon. I'm
>assuming that the assault cannon is .50 BMG or some derivative
>thereof,

I figured it for bigger: 20mm, maybe. Or the rather nasty Steyr 15.2mm
APDS round... except SR's assault cannon fire explosive rounds.

>and the Barret 121 is a .338 Lapua or similar. They have
>similar effects on people, but one is better Vs Vehicles than the
>other.

I figured the Shadowrun sniper rifles for firing big-but-slow subsonic
ammo, since you can't usefully silence them otherwise and that sort of
"elephant gun" calibre fits well with the monstrous damage but
relatively short range.

>> >From "Elven Fire", the "sniper rifle" is a .655 subsonic,
which makes
>> more sense in some ways for such a high damage code (though offhand I'd
>> make it 10D myself, and have HMGs at 15S base damage)
>
>It makes more sense to assume that the sniper rifle and HMG use
>different rounds, as I mentioned above. The .338 Lapua is more
>inherently accurate than .50 BMG. I also take anything out of the SR
>fiction as merely filler, rather than a canon (Cannon? ;-{>) source).

This was a scenario, not fiction, but I still don't think it definitive.

.338 Lapua goes subsonic (and loses accuracy) well before .50BMG, though
before that point I'll happily believe it's more consistent. Though,
.338 should be good (in the hands of an _incredibly_ good shot with
excellent rangefinder and solid met data) out to 1,200m or so.

.50BMG will go further, but with less consistency: it's used at those
ranges to destroy vehicles and aircraft, not to kill people.


>> Assuming you mean .303 Lee-Enfield, then the "standard" ballistic table
>> entry is for a 180-grain bullet at 2460 feet per second.
>>
>> .50 Browning Machine Gun is about 670 grains of bullet, at 2910 feet per
>> second.
>
>that sounds about right.
>over 3 times the mass, at 25% faster velocity.
>Probably closer to 4 times the energy.

2.3 times the energy. Still a big hike.


>
>Oh, and Paul, just a quick Q, did you ever do up game stats for all
>those 2057 RN ships you wrote up once?

Not yet, but I'm working on it. So much to do, so little time... :)


--
Paul J. Adam

Further Reading

If you enjoyed reading about Armor Penetration, you may also be interested in:

Disclaimer

These messages were posted a long time ago on a mailing list far, far away. The copyright to their contents probably lies with the original authors of the individual messages, but since they were published in an electronic forum that anyone could subscribe to, and the logs were available to subscribers and most likely non-subscribers as well, it's felt that re-publishing them here is a kind of public service.

Thwap!