I was discussing the pirate situation off Somalia with some sailors (civilian)
and someone made a comment that an RPG at 100 yards would be sufficient to
cause an immediate surrender.
Now ignoring the psychological component of having an RPG fired at you let's
consider the effectiveness of an RPG vs. a sailboat.
My thoughts:
Would an RPG warhead detonate against a fiberglass boat? I'm unclear on the
necessary impact needed to detonate one, but I wonder at whether or not a
warhead designed for impact vs armor would even notice a plastic boat hull on
it's way through.
Assuming the warhead detonated, what would be the probable effect of the
blast? Small hole? Big hole? What would be the difference if it was a steel
hull boat?
Assuming the attackers were operating from some sort of comparatively small
powerboat, would it be safe to fire an RPG from it? I understand they have a
significant backblast, which could endanger their own vessel.
Could you even hit a moving boat, from a second moving boat, under
open sea rollers? They're a comparatively low-velocity weapon with a
limited range. I think it would be exceptionally difficult to get a solid hit
that was anything other than luck, unless the firer was very
well trained (unlike most pirates/terrorists.) I mean the analog
would be firing at a moving vehicle, from a moving vehicle while going over
small hills.
FWIW, my comment was that I would be much more concerned by an automatic
weapon on a pintle, rather than an RPG as it's much harder
to dodge 400-500 rounds/minute (or more.) A Ma Deuce would make short
work of any small craft, and an M60 or M249 would also make for a very bad
day.
I know we have a lot of current and former military here, as well as
one combat engineer who is probably ready to go test this out. :-)
Bill
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lo--
 I'm not a military expert, but I've done a little sailing and know just
enough about fiberglass boats to be dangerous. :-)
 The original message has been snipped, excepting what I'll actually
address: Â Detonation. Maybe depends on the fuse type in the warhead? I don't
know much about RPGs. A sailboat of significant size has a fairly thick hull
of laid up fiberglass, and perhaps a balsa core into the bargain. It has to be
seaworthy, after all, and we're not talking about capital ship AP shells
failing to detonate against the plating of a jeep carrier,
leading to a through-and-through with no detonation.
 I would say there's a fair chance of detonation, with catastrophic local
delamination of the hull material. Fother it quick or blub blub blub goes your
boat. Â Hitting a moving boat: As Bill points out, getting a hit would be a
sporting challenge. Still, if you're in the sailboat and you don't have a
means of deterring the guy with the RPG, would you take the chance he had
more than one RPG and might roll the golden BB on his next try? Some might
(and it might even be prudent to do so), but I'd hardly blame you for heaving
to under the circumstances. Â For what it's worth. Â Best, Ken
> --- On Sun, 10/19/08, Bill Brush <bbrush@gmail.com> wrote:
Would an RPG warhead detonate against a fiberglass boat? I'm unclear on the
necessary impact needed to detonate one, but I wonder at whether or not a
warhead designed for impact vs armor would even notice a plastic boat hull on
it's way through.
Assuming the warhead detonated, what would be the probable effect of the
blast? Small hole? Big hole? What would be the difference if it was a steel
hull boat?
(snip) Could you even hit a moving boat, from a second moving boat, under
open sea rollers? They're a comparatively low-velocity weapon with a
limited range. I think it would be exceptionally difficult to get a solid hit
that was anything other than luck, unless the firer was very
well trained (unlike most pirates/terrorists.) I mean the analog
would be firing at a moving vehicle, from a moving vehicle while going over
small hills.
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hulls in most sailboats that are transatlantic capable are fairly substantial.
There's also a lot of hardware and inner content within those boats. I'm
pretty certain a hit would detonate. The impact of the hit would be dependent
on the warhead type. I believe some RPGs are HE, others are more into the
armour piercing realm, and still others may have fancier warheads.
HE would be bad news - hull damage, maybe sinking, plus possible blast
effects or shrapnel (even if just from your boat!) affecting crew members. If
they happen to hit the right place, they could dismast the boat
(maybe).
At the very least they could damage static and running rigging that may render
the boat incapable of maintaining way or incapable of steering. And you could
end up shipping water (maybe even a lot of it).
HEAP or the like might just punch a small hole through the boat. But then,
what might it hit on the way? Propane tank? Gas tank? Diesel tank? Various
other critical pieces? Batteries? etc. It would be less serious, but could
still leave you shipping water.
If you got more exotic warheads (don't know if RPGs can carry things like a
cannister charge), then your results would depend on warhead.
The pintle mounted DShK would also be bad news for the average sailboat (as
would an M2HB or even a good old RPK or the like).
And all they have to do is blow off your rudder, shred your sails, knock off a
mast, or wreck some rigging and you're out of commission and they're madder.
And bullets would tend to make the task of sailing the boat more challenging.
As to hitting: If they are in a motor launch, they'll be able to get up
alongside and there isn't much you can do unless you have one of those
superfast cats or a huge monohull. And then you've probably got a big enough
crew and maybe small arms of your own. If they get alongside, it isn't *that*
hard to predict where a sailboat will be. It might take 2 or 3 volleys, but
they may well have the ammo for that.
Sailboat, the choice is tough. I think I might well let them board and then,
if I though I had to have a go, take it when they're aboard and they've got
their people interspersed with yours and potentially weapons at hand to be
acquired. Definitely in the 'rather never try that, thanks!' end of things.
TomB
> On Thu, Oct 23, 2008 at 7:25 PM, Tom B <kaladorn@gmail.com> wrote:
I'd be inclined to say 'it depends' on a lot of factors. RPGs as
transported, stored, and operated by third-world savages tend to fail
to go off greater than half the time. I doubt Somali pirates hopped up on qat
are any better than Arabs. And that's shooting at actual armored vehicles.
A fiberglass hull may or may not detonate the pizeoelectric fuze.
> HE would be bad news - hull damage, maybe sinking, plus possible blast
And
> you could end up shipping water (maybe even a lot of it).
Various
> other critical pieces? Batteries? etc. It would be less serious, but
My concern on a fiberglass hulled vessel would be the probability that the jet
of copper would be at some really silly temperature (I'm sure OA could give a
precise reading) that would tend to ignite the boat. Not to mention unused
rocket fuel, etc.
> The pintle mounted DShK would also be bad news for the average
Not to mention the possibility of killing crewmen.
> As to hitting: If they are in a motor launch, they'll be able to get
RPG accuracy and precision is not all that great, they are intended to
hit slow-moving armored targets at close range from a stationary
platform (ie, the ground). However, as has been demonstrated, fire enough of
them at almost anything, and you can hit a helicopter. I doubt a sailboat is
going to be more difficult to hit than a Blackhawk.
> Sailboat, the choice is tough. I think I might well let them board and
I've got a better idea.
Don't go sailing around the Horn of Africa without an anti-piracy PLAN
that is more than "hope they don't board my boat".
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> Thu, Oct 23, 2008 at 1:25 PM, Ken Hall <khall39@yahoo.com> wrote:
> I would say there's a fair chance of detonation, with catastrophic
That is my take on the topic. Though the build and size of the boat a big
factors in how much damage will be done by and indivdual rpg. PBR2s and the
like have extensive use of flatation enhancing foam through out their void
spaces, to enhance their resistance to sinking due to pentration of the hull.
As for hitting a boat with one, that shouldn't be much different from hitting
a boat with a rifle. It really depends how much practice you have in the
environment, and boats tend to be larger than ground vehicles.
Note, small boat warfare was my MOS, so what I find reasonable may vary from
your average groundpounder.
> John Atkinson wrote:
> A fiberglass hull may or may not detonate the pizeoelectric fuze.
Agreed. Depends on far too many factors to say anything for certain... but the
risk that it would go off as intended is certainly big enough that I
wouldn't want to risk being hit by it.
> >HEAP or the like might just punch a small hole through the boat. But
Various
> >other critical pieces? Batteries? etc. It would be less serious, but
Not
> to mention unused rocket fuel, etc.
The jet temperature is fairly low; usually around 600 degrees centigrade or
thereabouts - the metal is actually solid, but under such extreme
pressure that it behaves roughly as if it were a fluid. Remaining rocket fuel
(if
any; most RPG rocket boosters burn out at fairly short ranges) and especially
the blast from the warhead are far more likely to start fires
than the copper jet is.
> RPG accuracy and precision is not all that great, they are intended to
Yeah. It'll be a fair bit trickier to hit a boat with an RPG than hitting with
a combat rifle due to the low velocity of RPG rounds.
> However, as has been demonstrated, fire
Most of those helicopters (including those in Mogadishu) weren't hit
directly though, but instead caught in the blast by self-destructing
RPG-7
rounds. The factory-set self-destruct range of RPG-7 rounds is 920
meters, but it isn't that hard to reduce it... if you don't mind risking
blowing
your hands off, that is :-/
Later,
> At 8:39 AM -0700 10/24/08, Evyn MacDude wrote:
Well follow-up shots are harder to effect with any rapidity. And from
water, you're on a pitching, rolling and yawing platform trying to hit a
pitching, rolling and yawing platform.
I would argue, that firing an RPG from a boat against another boat is no EASY
subject. Far easier when shooting at a large ship.
> Note, small boat warfare was my MOS, so what I find reasonable may vary
Ever fire anything that has a longer time of flight against another water
borne craft? Did you do it on open water and not on a lake or river?
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Resident GingerBeer said:
> I'd be inclined to say 'it depends' on a lot of factors. RPGs as
[Tomb] That's true. I was accounting for weapons in a good state of
repair.
> A fiberglass hull may or may not detonate the pizeoelectric fuze.
[Tomb] It may also bounce and rpg if it doesn't detonate. Those hulls
are tougher than most folks think. You'd need a heck of a lot of energy
applied at a pretty orthogonal angle to punch through with a dud of several
inches diameter. Get it off angle and it'll reflect off it does not detonate.
> My concern on a fiberglass hulled vessel would be the probability that
Not to mention unused rocket fuel, etc.
[Tomb] I wouldn't worry so much about the hull as I would the contents.
Stored goods, fabric bedding, the propane tank for the stove, the diesel tank,
any batteries, etc. All could ignite if exposed to enough temperature or even
in some cases explode I would think. If all the wooden inside decking of your
boat and the kitchen are afire, the hull is probably further down your list of
worries. But my point about the propane and batteries is you may also get
secondary explosions.
> And bullets would tend to make the task of sailing the boat more
> Not to mention the possibility of killing crewmen.
[Tomb] That fit under my definition of challenging sailing. :0)
RPG accuracy and precision is not all that great, they are intended to
hit slow-moving armored targets at close range from a stationary
platform (ie, the ground).
[Tomb] True enough. But if I can match your course at a distance of 15'
in
a motor launch and your target is 34'+ in length (nearing minimum
threshold for a transoceanic sail), I'm going to have a hard time missing.
Multiple
launchers and/or multiple shots will pretty much guarantee a hit.
> However, as has been demonstrated, fire
[Tomb] Bingo.
> Don't go sailing around the Horn of Africa without an anti-piracy PLAN
[Tomb] Honestly, sailing around some of those regions (Gulf of Aden,
Panama, Asia Pacific Rim, etc) in a small but valuable keelboat or catamaran
is
basically throwing the dice. There's no way, even if there are 4 - 6 of
you aboard and you do have firearms that you can reasonably stand off launches
with support weapons and RPGs. So, I can't really think of a "plan" that's
going to change that reality. You can mitigate risk of being noticed and
targeted, you can take some steps to offer limited defense portside or at
anchor or underway, but ultimately, you aren't in the kind of vessel and don't
have the kind of armaments to effectively resist. My answer is 'don't go
there'.
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> Fri, Oct 24, 2008 at 10:34 AM, Ryan Gill <rmgill@mindspring.com> wrote:
> At 8:39 AM -0700 10/24/08, Evyn MacDude wrote:
True,
> >Note, small boat warfare was my MOS, so what I find reasonable may
> Ever fire anything that has a longer time of flight against another
Yes, quite a bit of I had quite a bit of experience in coastal zones, and yes
slower weapons take some pratice....
But without practice, naw ya ain't gonna hit much.
> Tom B wrote:
[Tomb] Honestly, sailing around some of those regions (Gulf of Aden,
Panama, Asia Pacific Rim, etc) in a small but valuable keelboat or catamaran
is basically throwing the dice. There's no way, even if there
are 4 - 6 of you aboard and you do have firearms that you can
reasonably stand off launches with support weapons and RPGs. So, I can't
really think of a "plan" that's going to change that reality. You can mitigate
risk of being noticed and targeted, you can take some steps to offer limited
defense portside or at anchor or underway, but ultimately,
you aren't in the kind of vessel and don't have the kind of armaments to
effectively resist. My answer is 'don't go there'.
That got me thinking what a "random encounter" table for that part of the
world would be like, both on and off the water. Scary.
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Then of course there seems to be that trick from Afghanistan that made
them useable as a crude form of anti-aircraft weapon. Was that trick
previously covered on this list or another
> What trick, pointing them in the air, launching a lot of them, and
I used to paintball with a lad who'd served as an allied war correspondent
with the Mujahadeen during the war with the soviets. Before they got a
boatload of stingers, they had real threats from the Hinds. One of their
interesting tactics to utilize available gear was to lure the Hind into a
mountainous valley, conceal RPG gunners along the edges of the hills, and fire
RPGs down into the rotor blades. I seem to recall him telling me he'd watched
this occur and work successfully. He was also lethally quiet in woodsball and
had a deadly first shot. He said when Hinds were hunting you, you learned to
be quiet and fast or you might not still be around.
TomB
> TomB wrote:
> > A fiberglass hull may or may not detonate the pizeoelectric fuze.
An RPG round weighing several pounds arriving with a velocity of 2-300
m/s
has quite a bit of kinetic energy to apply, and all of it concentrated at the
point of the nose which is usually less than an inch across... and once the
point breaks through, it takes far less energy to widen the hole than
it would to create an instant several-inches wide breach.
> Get it off angle and it'll reflect off it does not detonate.
Don't bet too much on that. Several types of RPG rounds - I'd expect all
of
them, but don't know that for certain - are equipped with a biting edge
to ensure that they don't glance off even if they hit at quite acute angles...
and while those biting edges are there to increase the chances that the round
will detonate successfully, they also greatly improve the rounds' chances of
smashing through thin obstacles if they fail to detonate properly.
> RPG accuracy and precision is not all that great, they are intended to
...you'd better pray that you are inside the round's arming distance so it
won't detonate (or that it is a dud, giving the same result), because if it
does go off you'll get killed yourself when the round's rocket booster, fin
assembly and all other parts located behind the warhead come back at
high speed and hit you in the face.
Regards,
It's more than likely that the same RPG is involved in each attack.
Most civilians get nervous around pistols. Someone points a well known rocket
launcher at them and they'll bet flashes of every war movie they've ever seen.
Grenades that go off like 500lb bombs, pistol shots that blow a man off his
feet and 5 feet away, RPGs that blow up entire buildings.
The pirates want the vessel afloat so they can robit. If they want to sink it,
it's easy to hit a boat your stood on.
It's damned easy to make civilians surrender if you point an RPG at them.
The psychology behind it is MUCH better than the weapon.
> Bill Brush wrote:
I remember a sailing vessel I saw at a Harbor Days event. The owner dressed in
17th century grab and gave tours. He told the story of being boarded by the US
Coast Guard as he came north from Baja California and the inspector jokingly
asking if he had ammo for his 2pdr deck gun. The owner's straight faced answer
was "yes". Piracy only thrives when the pirates think they can get away with
it.
Michael Brown mwsaber6@msn
--------------------------------------------------
From: "Adrian1" <al.ll@tiscali.co.uk>
Sent: Friday, October 24, 2008 3:13 PM
To: <gzg-l@vermouth.csua.berkeley.edu>
Subject: Re: [GZG] Slightly OT - Hypothetical weapon question
> It's more than likely that the same RPG is involved in each attack.
I'd just say "Don't go sailing around the Horn of Africa" or any of
the other piracy hot-spots. Merchantmen may have to steam through
dangerous waters but yachtsmen don't have that excuse.
> On Fri, Oct 24, 2008 at 1:29 PM, Tom B <kaladorn@gmail.com> wrote:
> A fiberglass hull may or may not detonate the pizeoelectric fuze.
They are moving reasonably fast. They might simply stick into the hull and
wouldn't that be fun for the EOD tech?
> Not to mention the possibility of killing crewmen.
Without a necromancer on board.
> Don't go sailing around the Horn of Africa without an anti-piracy
that's
> going to change that reality. You can mitigate risk of being noticed
Personally, yeah, I don't see a reasonable plan that doesn't involve naval
escort. At a certain point in your planning process you pretty much have to
say, "This is a bad idea. Let's sail the Aegean instead."
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RPG round weighing several pounds arriving with a velocity of 2-300 m/s
has quite a bit of kinetic energy to apply, and all of it concentrated at the
point of the nose which is usually less than an inch across... and once the
point breaks through, it takes far less energy to widen the hole than it
would to create an instant several-inches wide breach.
[TomB] That's a good point too. I'm thinking about trying to force
several inches in diameter through a hull that can take the sizable sea
forces, but the contact point is a fair bit smaller.
> Get it off angle and it'll reflect off it does not detonate.
Don't bet too much on that. Several types of RPG rounds - I'd expect all
of
them, but don't know that for certain - are equipped with a biting edge
to ensure that they don't glance off even if they hit at quite acute angles...
and while those biting edges are there to increase the chances that the round
will detonate successfully, they also greatly improve the rounds' chances of
smashing through thin obstacles if they fail to detonate properly.
[TomB] Really? I've handled several of these (RPGs) and I don't ever
recall
noticing that. I do know that we used to have our M-72 rockets bounce
off the ground, terrain, obstacles, etc. If you got a good face on impact, you
got the detonation, but it seemed like if you didn't get a good shot with
the M-72 or the Carl Gustav, you could get a skipping miss. That's what
I saw on the range, whether this is typical of today's rounds is a whole other
story I suppose.
> [Tomb] True enough. But if I can match your course at a distance of
...you'd better pray that you are inside the round's arming distance so it
won't detonate (or that it is a dud, giving the same result), because if it
does go off you'll get killed yourself when the round's rocket booster, fin
assembly and all other parts located behind the warhead come back at high
speed and hit you in the face.
[TomB] Okay, call it 50' then Mr. Picky. At 50', I'd imagining you are
outside of a dangerous launch distance. And the 34' keelboat's side isn't
going to be a hard target at 50', even manouvering, because your launch is
faster and more manouverable if it is driven by anyone who knows what they are
doing.
> TomB wrote:
> >Get it off angle and it'll reflect off it does not detonate.
The biting edges I've seen have all been covered by softer materials
(softer than the hard steel of the edge, that is :-/ ) in order to
protect clumsy soldiers from cutting themselves while handling the round...
but they've nevertheless been sufficient to let the round cut through thick
plywood instead of bouncing off. It depends a bit on how much the round
yaws though - if it hits side-on, the biting edge won't strike the
target :-/
> >[Tomb] But if I can match your course at a distance of 15' in a
With those old rounds? You're kidding. Try 150'-200'... and you're not
100% safe from your own rounds even at that distance. (Particularly since your
own boat is a much bigger target for the rearwards-going shrapnel than
you yourself are.)
> And the 34' keelboat's side isn't going to be a hard target at 50',
Your biggest problem is getting the elevation right. A 34' keelboat hull
isn't particularly tall, and unless the sea is quite calm the boat you're
sitting in is rolling with the waves (especially if it is manoeuvring at
speed!)... if you're outside the round's danger zone it only takes a minor
unexpected wave at the moment of launch to send your round into the water or
through the target's sail (where it is very unlikely to explode even if it
works perfectly) instead of into the target's hull.
Later,
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Your biggest problem is getting the elevation right. A 34' keelboat hull isn't
particularly tall, and unless the sea is quite calm the boat you're sitting in
is rolling with the waves (especially if it is manoeuvring at speed!)... if
you're outside the round's danger zone it only takes a minor unexpected wave
at the moment of launch to send your round into the water or through the
target's sail (where it is very unlikely to explode even if it works
perfectly) instead of into the target's hull.
[TomB] I'm kinda surprised you need 150' stand off. I defer to your
domain knowledge, but that seems like quite a bit. I guess they are a fair bit
bigger than a hand grenade, but I've seen video of hand grenades going off
within 5' of people and them not taking shrapnel hits (Russians in Chechnya I
think). I know the RPG is bigger, but I hadn't expected that large of a lethal
radius.
As to the keelboat question: Depends a bit on your boat. I'd guess on the last
CS30 I was aboard, and it would have been marginally ocean capable, it
probably would have had a deck about 3-4 above the waterline and the top
of the cabin would have been about another 4' up. So you'd have about 8' to
work with and 30' in length. Of course, sail hits would be pretty marginal,
except any one of them could disable the boat because a sizable tear in
sailcloth combined with any sort of worthwhile wind can equal a destroyed sail
in fairly short order. There's a small chance of a mast or rigging hit.
Hitting a beneteau or other cover over the rear cockpit is a bit more likely
and they sometimes have a bunch of metallic infrastructure that might deflect
the round down I'd imagine.
Still, at 200', it might be a tricky shot. You might have to shoot a fair few
times. Every time I see videos of these sorts of guys, they've got
3-4
RPG rounds with them.
And as someone else pointed out, the threat might be enough. As a
psychological weapon, the RPG might be fairly concerning. It isn't how likely
the hit is, even if each shot was only 1 in 8, if he fires 4 shots, he's going
to have a decent chance of landing one and one is likely enough to cause a big
problem.
Of course, the small arms alone could kill your crew with some facility at
200m and a bunch of bullet holes would help neither the crew, the hull, the
sails or (if they were concentrating on the rear of the boat) your diesel or
the rudder.
I was reading about the French raid where they dropped a flag officer (cmdr of
their SF I think) into the water to put him in place to command a
raid -
flew him straight there, dropped him in the drink (technique the French
practice) and fished him out. The french SOF are interesting - be it
GIGN or the Commando Swimmers. And they seem willing enough to rumble with
pirates and to do things to rescue captured French citizens. Glad to see this
whole
situation getting some Int'l attention and maybe some anti-piracy
enforcement.
T.
> On Sun, Oct 26, 2008 at 5:56 AM, Tom B <kaladorn@gmail.com> wrote:
> [TomB] I'm kinda surprised you need 150' stand off. I defer to your
You don't--and are exceedingly unlikely to hit ANYTHING at that range.
At least, from what I've seen. Most of the time RPGs are fired under 100m, or
they are used for harassing fire because between the limits of the shooters
and the limits of the weapon, you won't hit any moving targets.
As a matter of fact, the US Army did a study once that gave it a 51% chance of
hitting a target at 200m that was moving at 9mph in a straight line. On a
firing range while no one was shooting back and you could take your time to
aim.
> As to the keelboat question: Depends a bit on your boat. I'd guess on
to
> work with and 30' in length. Of course, sail hits would be pretty
Yeah, but the 'up and down' on the firing platform could induce pretty
sizeable errors, while only the cross-winds and relative speeds of the
boats induce a margin of error front and back.
> except any one of them could disable the boat because a sizable tear
Well, the sail would definitely not detonate the warhead.
> sail in fairly short order. There's a small chance of a mast or
Or detonate it. And I bet the frag off of the OG-7 would penetrate,
never mind the PG-7 warhead.
> John Atkinson wrote:
> > [TomB] I'm kinda surprised you need 150' stand off. I defer to your
"Danger zone" =|= "lethal radius". The lethal radius is the radius where
you (supposedly) run a 50% or higher risk of dying, ie. the zone where the
shooter wishes the target to be when the round detonates. The danger zone OTOH
is the zone where you (even more supposedly) don't run *any* risk of getting
hit by fragments from the round, ie. the zone where the gunner wants to be
*himself* when the round detonates.
And yes: RPG warheads are considerably bigger than hand grenades, and the big
fragments from RPG fin assemblies etc. tend to go considerably further than
(and are dangerous at considerably longer distances as) hand grenade shrapnel.
FWIW this is a major problem for us at work, since certain customers of ours
want to cut the arming distances of our products *waaayyy* shorter than we're
able to guarantee that their gunners won't kill themselves <shudder>
> You don't--and are exceedingly unlikely to hit ANYTHING at that range.
Um, John... last time I checked 150' was less than half as far as 100m. But
maybe you Americans have much bigger feet than the Imperial ones I'm used
to? ;-)
> > except any one of them could disable the boat because a sizable tear
Agreed (...OK, not to 100% since some of those old rounds could go off at even
the merest hint of an impact <shudder>), but even the round passing
through it would cause a big enough tear in the sail to allow the wind to
destroy it eventually.
Later,
> At 6:56 AM -0400 10/26/08, Tom B wrote:
Part of the problem with an RPG and similar is that the base of the rocket is
more or less launched back at you by the explosion of the warhead. It's not
very aerodynamic, but it has a lot of velocity from that nice neat explosion.
On Sun, Oct 26, 2008 at 10:18 AM, Oerjan Ariander
> <orjan.ariander1@comhem.se> wrote:
> And yes: RPG warheads are considerably bigger than hand grenades, and
"Gosh, I thought it was a directional explosion... "
Something like that? Hehehe...
Of course, Third Worlders are notoriously cavalier about such
things--I believe the cultural concept is denoted by "Inshallah".
Inshallah, I will kill the Americans. Inshallah, I will blow myself up.
Inshallah, the RPG will be a dud, but I will go to the hashish bar and brag
about how manly I am for firing an RPG at the Americans.
> You don't--and are exceedingly unlikely to hit ANYTHING at that range.
Feet... right. Feet. Excuse me while I go flagellate myself. I'm used to
thinking in meters so much that my eye glossed right over the little '. I just
assumed that a European would be using meters.
> At 4:00 PM -0500 10/26/08, John Atkinson wrote:
Little realized fact about Shaped charges. They' still an area effect weapon.
Things to the side and rear...not so nifty a place to be for the given
quantity of explosives.
> Inshallah, I will kill the Americans. Inshallah, I will blow myself
You guys need to get sensors and listening gear in the HAshish bars. Though
how much of what you guys would get would be bravado and balderdash would
probably make it poor as an intel source.
> Feet. . . right. Feet. Excuse me while I go flagellate myself. I'm
TomB is a fellow USian I believe.
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> Sun, Oct 26, 2008 at 7:32 PM, Ryan Gill <rmgill@mindspring.com> wrote:
> >Feet. . . right. Feet. Excuse me while I go flagellate myself. I'm
Actually, I do believe he is most assuredly Canadian. ;-)
Still NAC, though. :-D
Mk
Well, some of NAC is European...
I suppose we have to say TomB is an American, just not a 'Merican.
Wait, Canadians made me drive in KM's, but use feet in common discussion?!?!?
Oh, yeah, he was prolly talking down to his dimwitted southern
neighbors. ;->=
The_Beast
Indy wrote on 10/26/2008 10:44:08 PM:
> On Sun, Oct 26, 2008 at 7:32 PM, Ryan Gill <rmgill@mindspring.com>
wrote:
> >Feet. . . right. Feet. Excuse me while I go flagellate myself. I'm
> TomB is a fellow USian I believe.
> At 7:20 AM -0500 10/27/08, Doug Evans wrote:
Just no 'continental'.
> I suppose we have to say TomB is an American, just not a 'Merican.
Probably not. Some Canadians remember the days of the Red Ensign and Canada
having more navy than say, oh, Thailand.
> On Mon, Oct 27, 2008 at 5:20 AM, Doug Evans <devans@nebraska.edu> wrote:
I believe that it is just using units that most of the readers will
understand. Contributing factors are entering school before 1975 (I think TomB
and I are rough contemporaries[we gamed irregularily, when I was in Ottawa]),
when the changeover happened, and how much inertia pounds and feet have.
Gallons disappeared rather quickly, replaced by smaller four litre jugs (our
gallons were the volume of ten pounds of water, not eight). It was also handy
for gasoline retailers as it fended off the dreaded extra digit in the price
for just over two decades. Meters are not useful for describing heights of
people as
If memory serves, Canada went metric around 1976 (silver jubilee?), and that
would put TomB in about grade 2 at that time. So while his formal schooling
would have emphasized the metric system, his parents (and even peers just a
few years older than him (I'm looking at you, Jimbo)) would be conversant
primarily with Imperial units, and so there's good exposure to both.
Most Canadians my age / TomB's age can easily convert common linear
measures, volumes, temperatures and weights on the fly (3m = 10', 4 L ~
1 US gallon, 331 ml beer is called a pint, *9/5+32, 0.9 kg ~ 2 lbs).
That said, I was tripped up at Thanksgiving (which is recently past in Canada)
on the conversion from litres to gallons... I knew the US gallons number, but
not the other.
> -----Original Message-----
On Mon, Oct 27, 2008 at 12:29 PM, McCarthy, Tom (xwave)
> <Tom.McCarthy@xwave.com> wrote:
That would be right. I started high school that year. In Geography, each day
we started the class by taking a ruler and neatly crossing out imperial
measurements and changing it to metric. This was to bring the older text books
"up to date".
My dad was a carpenter and joiner. He always did everything in imperial, even
after the change. I don't know about now, but up until 10 years ago I know
that wood, etc. was still sold in imperial units: 2 x 4s in 10 and 12 foot
lengths, etc. He grew up with Imperial, of course, but he preferred imperial
measurements. He couldn't find a tape measure in metric to the 10ths of a
millimetre at the time, or even to half a millimetre. Maybe you can now. He
could find tape
measures out to 1/64th of an inch (roughly 0.4 of a millimetre) and
tape measures to the 1/32 of an inch (0.8 of a millimetre) were
common. For him to switch to metric would have meant working in unacceptably
large tolerances.
> Most Canadians my age / TomB's age can easily convert common linear
This ability fascinates my American wife. :-)
> On Oct 27, 2008, at 1:29 PM, McCarthy, Tom (xwave) wrote:
> If memory serves, Canada went metric around 1976 (silver jubilee?),
One thing I've had lots of fun converting back and forth from is Imperial
weights to US weights. They're different outside of pounds. Hundredweight and
Tons (long and short).
Not usually an issue unless you're referring to the manual for an armored car
trying to figure out how much it should weigh (aside from whether or not it's
been "bombed up" or not). Hmm, Weight of a Daimler Armoured car..., 7.5 tons
in weight. that's probably Long Tons, which really means, it's 16,800 lbs, NOT
14,000 lbs. That 2,800 lb difference can be significant enough to be a large
cost difference (Or fine difference if you're overweight on the highway).
Of course the difference between being loaded up for fighting the Hun and
being empty in display form, can be significant. The Humber Armoured car can
have up to 70 rounds of 37mm AP and HE plus around 3000 rounds of 7.92mm on
board and we'll never have that much, so there's not as much issue to having
the "full" weight available for transport....BUT....one never knows...
Quick, some one tell me the cargo capacity of a British 15cwt truck. ;-)
What's even more fun is talking Miles, yards and degrees in
navigation with the Yank Re-enactors who are using Mils and trying to
use meters because they're thinking in Modern US Army speak....
"Meters old boy? I don't think the Kings Regulations use Meters as a standard
unit of measure..."
> John Atkinson wrote:
> >And yes: RPG warheads are considerably bigger than hand grenades, and
Sometimes I get that impression, yes... though I wouldn't laugh about it if
I were you :-/
> Of course, Third Worlders are notoriously cavalier about such
...yeah, but those particular customers of ours I'm thinking of aren't Third
Worlders...
> >>You don't--and are exceedingly unlikely to hit ANYTHING at that
Plenty of European tabletop gamers are surprisingly fluent in the smaller
Imperial measures of distance since the rules we grew up with were English
ones from before the conversion <g>
Later,
> Richard Bell wrote:
> Meters are not useful for describing heights of people as
Not awkward at all. For example, my height is one-seventynine... that's
even easier to say than the Imperial equivalent five-foot-eleven :-)
Later,
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> >Feet. . . right. Feet. Excuse me while I go flagellate myself. I'm
[TomB] Although flattering, and although I do have an affinity for the
large number of my friends down there, I am Canadian. I do lean a bit right
for our country, but that still makes me pretty middle of the road by USAian
standards.
Mr: Kochte:
Actually, I do believe he is most assuredly Canadian. ;-)
Still NAC, though. :-D
[TomB] Or the dreaded splinter group "Scottish-Canadian".
[TomB] Mr. McCarthy is right, I grew up mostly in metric, but my Dad had
a sign in the garage that read "English spoken here. Feet and not meters.
Gallons and not litres. Pounds and not kilograms." and he called the Maple
Leaf 'Pearson's Liberal Banner'. The only Canadian flag he'd acknowledge is
the Red Ensign.
[TomB] From the top of my head: 1" = 25.4mm, 1m = roughly 39", 1 quart =
946 mL (at least as they sell motor oil), 1 US gallon = 4 liters (UK gallon
=
4.5, Canadian Gallon = 4.55). 1 Canadian Dollar = an inexplicable 0.82 USD. 1
km = 0.62 miles, 1 metric ton = 2200 lbs, 1 Stone = 14 pounds, 1 chain = 6
feet, 500mL = 1 guiness, 12 dogs = 1 sled, and 1 Mountain Dew = 0 caffeine.
[TomB] Metric makes sense for any form of engineering math. But for
describing people's height and weight, Imperial seems more intuitive. Same
with shopping for food in pounds, although liters make sense for liquids.
Speeds in mph or km/hr are fine. Sailboats are measured in feet and
anyone who tells me I'm 1.62m tall leaves me with a blank expression.
[TomB] 2 + 2 = 5 if you are using a metric 2.
On Mon, Oct 27, 2008 at 3:20 PM, Oerjan Ariander
> <orjan.ariander1@comhem.se> wrote:
> "Gosh, I thought it was a directional explosion. . . "
It's only funny because most of the folks who kill themselves off in this
manner will be Infantrymen, rather like a bunch I got into a screaming
argument with during an AAR about why we don't have dismounts on the the
ground within 300m of a MICLIC charges. Fortunately it was a notional one, or
everyone between the Company Commander and the Divisional Commander would have
been relieved, and maybe more folks.
> On Oct 27, 2008, at 5:15 PM, Tom B wrote:
Based on the interaction I've had with NON Montreal and NON Toronto type Latte
snarfing Canukistani's, they're pretty much middle of the
road for USians who aren't of the New York/Chicago/DC/LA Latte
snarfing sort.
Most of the time they seem to have been associated with folks who were in the
"Canned Forces" miserableness.
> [TomB] Or the dreaded splinter group "Scottish-Canadian".
Ahh, the evil overlords of the French Canadians... Nearly to a Man those of
Canada who were decidedly PRO crown for years.
> [TomB] Mr. McCarthy is right, I grew up mostly in metric, but my
Aye, that's the sort.
> [TomB] From the top of my head: 1" = 25.4mm, 1m = roughly 39", 1
What about hundredweight!!!
*ahem* Latte snarfing Nebraskan here!
Oh, ok, I almost never adulterate good espresso with anything like that much
dairy, but I'm occasionally forced into a Starbucks, and there's NO good
espresso there...
Damn, another slippage of topic. ;->=
The_Beast (who wandered off completely...) (Can we ever have enough
ellipses?)
Ryan Gill wrote on 10/27/2008 06:43:05 PM:
> *** massive snippage here *** they're pretty much middle of the
On Mon, Oct 27, 2008 at 6:43 PM, Ryan Gill <rmgill@mindspring.com> wrote:
> Based on the interaction I've had with NON Montreal and NON Toronto
(At the risk of continuing the off topic discussion), living in the Deep
South, I can safely say that while Tom is to the right of most Canadians, he's
very much to the left of most Bible Belt USians.
> At 8:42 AM -0500 10/28/08, Doug Evans wrote:
It happens. It always wanders back like a homing torpedo trying to acquire a
target. We went from gaming, to RPGs and their danger area, to inches and
meters and feet, USians & Canukistanis, latte drinking Toronto type
Canukistanis, back to inches and cm and their relevant scope within
gaming...To meta topics about subject matter...
> The_Beast (who wandered off completely...) (Can we ever have enough
Not if you're programming in Lisp.
http://en.wikipedia.org/wiki/Lisp_programming_language
> John Atkinson wrote:
> >>"Gosh, I thought it was a directional explosion. . . "
It might be funny if the persons demanding those insanely-short minimum
arming distances were the same ones who will actually, personally use the
weapons in question. If that were the case, they'd really only have themselves
to blame when they get a fin assembly stuck in the forehead.
Unfortunately, the people making those demands *aren't* the end users of
the product, and thus will never personally have to suffer the effects of
their demands >:-(
> At 6:32 PM +0100 10/28/08, Oerjan Ariander wrote:
> Unfortunately, the people making those demands *aren't* the end users
Hey, stop taking our Beltway Bandits!
Oh, wait! What am I thinking?!!
Take more of them. Want the Future Combat System project?
Guys, this thread has been great. I don't know where else I could consult with
combat engineers, sailors, weapon designers, and a slew of other backgrounds
all in one convenient forum.
I think ultimately the conclusion of "stay away from pirate zones" is the best
advice, but it's good to see that I'm not totally off base in my assertion
that an RPG would be a difficult weapon to use against a boat from another
boat.
As a scenario, you could put a team of commandos on a sailboat
"q-ship", and team of pirates in a powerboat. A sailboat with a
popup/camoflaged stabilized 20mm cannon could be all kinds of fun.
That could be fun and different. For you combat types, if YOU had to sail
around the Horn of Africa, what would be your plan? Assume a 40'
yacht, small crew or single-hand, and no support vs. one boat of
pirates containing 8 pirates, armed with 2-3 RPG's, AK-47's, and M-16
knockoffs. For whatever reason surrendering the boat would be an
unacceptable option.
As a minor threadjack, anyone have any opinions on the practicality of
shooting a boat below the waterline at range? The figure bandied about was 2
ft (roughly 60 cm for the metric people). Based on the Mythbusters tests we
were of the opinion that high velocity rifles wouldn't be effective but
shotgun slugs might be providing you don't try to go too far below the
waterline and from too far away. Any naval weapon capable of this short of a
torpedo or a battleship class gun?
Bill
On Tue, Oct 28, 2008 at 12:32 PM, Oerjan Ariander
> <orjan.ariander1@comhem.se> wrote:
On Mon, Oct 27, 2008 at 8:53 AM, Ryan Gill <rmgill@mindspring.com> wrote:
> At 7:20 AM -0500 10/27/08, Doug Evans wrote:
> At 2:11 PM -0500 10/28/08, Bill Brush wrote:
An M2 50 Caliber would be ideal. You have automatic fire for walking rounds
onto the target and enough power to hole both sides of the hull below the
water line OR make one hole and crack the block of the engine. That's just
using ball OR AP rounds. Combine in some Tracer and API and you get nice
flames too.
That'll work on anything from a Go-fast boat to a destroyer if you catch
the destroyer's crew napping. (Look at how the British Royal Marines led by
Fairly Famous Mills worked over the Argie Frigate Guerrico at South Georgia
Island).
http://www.britains-smallwars.com/Falklands/South-Georgia.html
> At 12:59 PM -0700 10/28/08, Richard Bell wrote:
Yeah but today, Thailand has more. Heck they have an Aircraft Carrier. HMCS
Bonaventure was broken up in what 1970?
> It may have consisted of mostly convoy escorts and light cruisers, but
Second Largest Airforce, third largest Navy.
On Tue, Oct 28, 2008 at 2:53 PM, Ryan Gill <rmgill@mindspring.com> wrote:
> An M2 50 Caliber would be ideal. You have automatic fire for walking
In the Mythbusters episode that was mentioned they found that.50 cal round
pretty much disintegrated into nothing when shot into the water. That.50 cal,
based on that data, may not be able to put a hole in the boat very much below
the water line (a few inches at most).
Thought I'd bet you would hardly care since the M2 is likely to punch holes in
everything else above the water line without much problem.
Here in Australia (or at least Sydney) heights are invariably measured and
written in centimetres, but *spoken* as if they were
metres. For example I am "one seventy-five".
It isn't metric or imperial that drives me up the wall, but occasions
when stupid pseudo-measurements are used when perfectly good units of
volume and mass are available. For example, I was recently asked by my doctor
to participate in a NSW Department Of Health survey, which asked me, among
other even more deranged things, how many "cups" of fruit, vegetables and
salad I ate each day. Cups? How the *bleep* do you measure a cup of apple,
asparagus, lettuce or broccoli? Put it
through a blender and reduce it to baby-food?
> Ryan Gill wrote:
> >Unfortunately, the people making those demands *aren't* the end users
Well, the FCS is unlikely to ever see combat, so in its case it probably
won't matter much if the requirements don't make any sense... :-P
> Ryan Gill wrote:
> >As a minor threadjack, anyone have any opinions on the practicality
Doubtful, since its rounds would also break up pretty quickly after entering
the water. (OK, the Mythbusters didn't include a.50 HMG, but they
did test a .50-caliber sniper rifle, and its bullets behave pretty
similarly to the HMG's when they strike water.)
> You have automatic fire for walking rounds onto the target and enough
> power to hole both sides of the hull below the water line OR make one
No mention of small-calibre rounds causing *underwater* damage there...
the Carl Gustaf tore up a serious hole just above the waterline (big enough
for waves to get in), and the Guerrico's superstructure and upper hull were
pretty badly riddled, but the underwater hull was essentially intact.
Later,
> On Oct 28, 2008, at 3:01 PM, Ryan Fisk wrote:
If the ballistics info in "Kaigun" is correct, a shell striking the water at
17 degrees and with a flat head is optimal for underwater penetration. And
that's also assuming the IJN wasn't completely nuts with the concept.
> At 4:01 PM -0600 10/28/08, Ryan Fisk wrote:
wrote:
> An M2 50 Caliber would be ideal. You have
What were they firing? AP is not going to disintegrate. Don't base your
ballistics knowledge on Mythbusters. They're NOT very expert on Ballistics.
One thing to contemplate is that at range you're going to have some downward
arc on the rounds. If they impact at the waterline on a boat, what distance
below the water line are they going to then pass through?
> Thought I'd bet you would hardly care since the M2 is likely to punch
Everything Above, and below as it's going to keep on going barring something
REALLY solid like an engine block and that's not going to like acting as a
stop for.50.
> At 11:24 PM +0100 10/28/08, Oerjan Ariander wrote:
Of course not, with the Network centric nature of the system, it'll be inside
the OODA loop of the enemy that we'll have won without firing a shot.
You're clearly not up on the transformative nature of distributed data
networks and their
effect on warfare in the future. :-D
> At 11:40 PM +0100 10/28/08, Oerjan Ariander wrote:
the sniper rifles can only really fire ball. They can't fire the SLAP rounds.
Were they testing the API or AP rounds? Ap is going to have a lower sectional
density and WILL yaw when it strikes the water BUT it's not going to break up
very well.
> of small-calibre rounds causing *underwater* damage there... the
Yep. The MG and SLR fire didn't do well for the 40mm crew or other crew trying
to respond to damage control efforts. Ain't much armor on a Destroyer.
On Tue, Oct 28, 2008 at 7:29 PM, Ryan Gill <rmgill@mindspring.com> wrote:
> At 11:40 PM +0100 10/28/08, Oerjan Ariander wrote:
As I recall they were using civilian standard full-metal jacket
rounds. Copper by appearance.
On that myth they were testing to see how far under water you needed to be to
be "safe" from being shot at. Essentially all the
high-velocity modern rifles disintegrated on impact with the water.
Special use military rounds may hold together better but I suspect that a
great deal of their kinetic energy is going to be spent in a very short
distance.
Bill
On Tue, Oct 28, 2008 at 4:29 PM, Michael Llaneza
> <maserati@speakeasy.net> wrote:
On the practical side if I had to travel through that area.
I would use a.50 cal sniper rifle from the cabin to go for disabling hits to
the engine. I would make sure that I had some armor for the
cabin and cockpit. Another sniper in .308 for anti-personnel. I know
that the boats will both be moving and make the shots hard. Shoot more then.
If you can disable the motor of the pirate launch before they can close then
you can sail away.
Close in would be grenades and automatic weapons.
All of this assumes that capture would mean execution.
Bob Makowsky
----- Original Message ----
From: Bill Brush <bbrush@gmail.com>
To: gzg-l@vermouth.csua.berkeley.edu
Sent: Tuesday, October 28, 2008 3:11:44 PM
Subject: Re: [GZG] Slightly OT - Hypothetical weapon question
As a scenario, you could put a team of commandos on a sailboat
"q-ship", and team of pirates in a powerboat. A sailboat with a
popup/camoflaged stabilized 20mm cannon could be all kinds of fun.
That could be fun and different. For you combat types, if YOU had to sail
around the Horn of Africa, what would be your plan? Assume a 40'
yacht, small crew or single-hand, and no support vs. one boat of
pirates containing 8 pirates, armed with 2-3 RPG's, AK-47's, and M-16
knockoffs. For whatever reason surrendering the boat would be an
unacceptable option.
Bill
> At 11:21 PM -0500 10/28/08, Bill Brush wrote:
> From what I understand is that different rounds
Bullet integrity is strongly linked to not only the target struck, the speed
at the time of impact of the bullet but also towards how the manufacturer
designed and constructed the bullet. Some will fragment quickly, others will
not.
Take a look here and pay particular attention to the exhibits at the bottom.
http://www.firearmstactical.com/wound.htm
In the context of.50 bmg, I'd expect some API and AP in the mix for marine
use. Those may yaw, but aren't going to break up nearly as quickly. Also, by
the time they do start to break up, you're still going to have problems with
the fragments carrying some velocity. More over, if it does yaw in the water,
that just means it's going to key hole the hull side and not just make a nice
neat.5" hole.
On Tue, Oct 28, 2008 at 6:23 PM, Ryan Gill <rmgill@mindspring.com> wrote:
> At 4:01 PM -0600 10/28/08, Ryan Fisk wrote:
> In the Mythbusters episode that was mentioned they found that .50 cal
No argument there. They don't have a clue, but the footage they shot was very
convincing. I would have NEVER expected the result as seen on camera.
As for AP, I have no idea.
When it comes to ballistics, I go with this book:
http://www.amazon.com/Understanding-Firearm-Ballistics-Robert-Rinker/dp/
0964559846
It's not very scientific, but I shoot the crap out of stuff in my back yard
too. I live in rural Wyoming, I have tons of back yard.
> On Wed, Oct 29, 2008 at 9:05 AM, Ryan Fisk <ryan.fisk@gmail.com> wrote:
wrote:
> At 4:01 PM -0600 10/28/08, Ryan Fisk wrote:
I guess I don't consider this a "ballistics" question, so I fail to see how
whether or not they're experts on ballistics is relevant. They were testing
weapons within the constraints of the myth and testing parameters that were
reasonable. I've seen this implied disdain of them (the Mythbusters) on a few
occasions and I have to say I don't "get" it. They're not experts, they don't
purport themselves
to be experts, but they take questions that have non-obvious answers,
and test them in a scientific and entertaining manner. The whole point of the
show is to entertain while testing things based on the scientific method. It's
on the DISCOVERY channel, and unlike a lot of programming they actually work
at discovering answers. If science class in school was half as interesting
we'd have a lot more kids interested in hard science.
They'll even say that the myths where they get an unexpected result are the
ones they like the best.
It would be interesting to see if a gun/bullet/charge combination
could be found that would penetrate water reliably. Anyone have a pond and a
sheet of plywood to test on?
Bill
> Ryan Gill wrote:
> >Doubtful, since its rounds would also break up pretty quickly after
Yes, the.50 sniper rifles can fire SLAP. Unfortunately doing so with the
muzzle brake still attached to the weapon will usually result in the muzzle
brake being ripped apart, which is why firing SLAP from the M107 sniper
rifle is specifically prohibited :-/ (If you remove the muzzle brake the
rifle will survive firing SLAP, but OTOH your shoulder might not like it
that much...)
> Were they testing the API or AP rounds?
Doubtful.
> Ap is going to have a lower sectional density and WILL yaw when it
You might be surprised at how badly AP penetrators can behave in water. Being
homogenous gives surprisingly little protection against breaking
up :-(
Later,
> At 1:56 PM -0500 10/29/08, Bill Brush wrote:
Bullets going through materials is a ballistics question with a LOT of
materials science issues thrown in for good measure.
> They were testing weapons within the constraints of the myth and
The trick is that I can take ONE load of ammunition or even three or
four of NATO spec .223/5.56x45mm and fire it into a block of ballistic
gelatin and get a clean bullet yaw and tumble. I can take another NATO spec
.223 load and fire into the same batch of ballistic gelatin and have the
bullet yaw and come apart in a near explosive fashion.
The point is, that their tests, are supposed to be the final word and many
people take them as such and when it comes to certain things they're not.
I've had a guy who builds radar systems which represent Soviet or other
"red force" radar systems from parts and 'other' data for _purposeful_
US military testing. He's looked at some of their shows and disagreed with
their methods. He does this as someone who innately understands the
fundamentals of RF propagation, wave guides, high power systems and
electronics. I'll trust his wisdom on certain subjects a LOT more than I will
the two guys in Mythbusters.
Fundamentally, some of their tests are utter balderdash.
> It's on the DISCOVERY channel, and unlike a lot of
I'm not saying it's not interesting, I'm saying that JUST because the two guys
on the Discovery Channel say it's so, doesn't mean it's always so.
> It would be interesting to see if a gun/bullet/charge combination
Yeah, in short go with a bullet with denser or more solid Jacket and lead core
construction. Or go with a bullet with a different sectional density (same
thing) AND different ballistic coefficient. The ogive is going to be in a
different place and depending on the way the bullet is shaped it may not yaw
at all. There's a Lot more to making bullets than just dropping a dollop of
lead in a mould that's been coated with copper.
Look
> At 8:11 PM +0100 10/29/08, Oerjan Ariander wrote:
That's why I said they couldn't fire SLAP. "repeatability" is a
fundamental and implicit point. ;-)
Personally I don't want to be anywhere NEAR anything with as much energy as a
.50 BMG where there's issues with things coming off the Muzzel. Not unless
I've got a nice THICK armoured glass panel between me and the weapon.
> >Were they testing the API or AP rounds?
> You might be surprised at how badly AP penetrators can behave in water.
Well, in high speed ballistics test on things like steel core ammo vs
expanding ammo, the steel core stuff doesn't do all that much. Look at how a
7.62x51 bullet behaves in a block of gelatin vs a smaller faster round. I
suspect it's also going to depend on where the core is as compared to the
Lead. Is the Steel 'core' out front backed up by the lead (not really a core?)
or is it a different round with the steel core along the entire length? How
solid is the jacket? Where the weight is as compared to the ogive of the
bullet will affect how it behaves.
I expect a number of AP types will just start yawing and loosing energy as
they go through the water. Too deep and it's going to loose too much energy,
regardless of fragmentation or not. I'm sure there's a sweet spot where the
rounds will still have enough energy to punch holes below the water line and
keep on trucking into the lower part of the other side.
Either way, being in anything short of an Armoured Cruiser or purpose built
armoured Monitor while someone fires.50 BMG at it is NOT my idea of a good
place to be. If all I have is an RPG or an AK, I'm going to call it a VERY bad
day.
> Richard Bell wrote:
Heh Hem.
> Bill Brush wrote:
> It would be interesting to see if a gun/bullet/charge combination
That's easy; Mythbusters did it on the show, too. Big, heavy, and most
importantly *slow* bullets - eg. old large-calibre musket lead balls -
go quite far in water without breaking up. Low speed is the key.
Later,
On Wed, Oct 29, 2008 at 6:39 AM, Ryan Gill <rmgill@mindspring.com> wrote:
> From what I understand is that different rounds
Agreed.
> Some will fragment quickly, others will not.
In gelatin. I am unaware of any firearms round designed for firing through
water from air, though I understand some special forces have firearms (and
rounds) designed for underwater use, I'm not aware of any that are designed
for shooting through water after being fired above it. This is more a
statement of my ignorance of such things
than of their non-existence, but I try to be well-read.
> Take a look here and pay particular attention to the exhibits at the
"Our goal is to instill a healthy attitude of skepticism in you so you're not
as willing to believe everything you read. Hopefully, you'll learn enough here
such that you'll be able to evaluate the
qualifications of so-called ballistics experts."
The above is the best part of the entire page, but firearms tactical is an
excellent resource.
"The entire missile path is captured in one or more 25 x 25 x 50 cm blocks of
10% ordnance gelatin at 4�C. The penetration depth, projectile deformation
and fragmentation pattern, yaw, and temporary cavity of the missile in living
anesthetized swine tissue are reproduced by this gelatin"
gelatin!= water (and, gelatin!= reality, but it's the best we have short of
shooting living beings in tightly controlled scientific experiments, something
frowned upon nowadays)
You can't generalize the gelatin results to behavior in water. There may be
some correlation, but that's just speculation.
> In the context of .50 bmg, I'd expect some API
I don't think we have enough data to come to that sort of conclusion.
Unless you have access to an API and/or AP water test you aren't
sharing. My very barely educated _guess_ is that shape and velocity
have more to do with water penetration than material composition, based on the
very small data set we have.
That all said, if I had a rifle or MG and I needed to punch holes below the
water line from above the water line, I'd sure give it my best try and I would
surely use AP rounds over something else as my first choice, but I wouldn't be
surprised if it didn't work.
> At 8:20 AM -0600 10/30/08, Ryan Fisk wrote:
Through water, no, but what were the rounds used on Japanese and German
shipping by US B25s and Bristol Beaufighters? That seemed to do RATHER well at
riddling them with holes and otherwise making life horrible for the Axis
crews. Sinking from the Rockets and Machine guns. The Mosquitos of RAF Bomber
and Coastal Commands also did rather well against German E Boats.
> gelatin != water (and, gelatin != reality, but it's the best we have
No, but I can point out that .50 is still used in anti-shipping and it
was effective in WWII in Anti-shippong purposes. If it were found
wanting, it would have been replaced with larger pedestal mount cannons for
close ship security with more optimized ammunition (there are PLENTY of
Oerlikon guns and mounts with roughly the same size as the.50s. It has not.
the point of the Gelatin test was to observe that two apparently similar NATO
5.56 loads behaved in extremely different ways under VERY similar
circumstances.
Sorry I haven't replied until now; real life is a bit busy :-(
> A long time ago, Ryan Gill wrote:
> >In gelatin. I am unaware of any firearms round designed for firing
> shipping by US B25s and Bristol Beaufighters?
US B-25Gs and Hs used 75mm explosive shells. Those particular models
were
developed specifically for anti-shipping strikes, presumably because the
nose-mounted 0.50" gunpacks in earlier B-25 variants were considered
insufficient for the task.
The Beaufighter's main armament consisted of four 20mm Hispanos in the nose.
While some marks of Beaufighters also had four 0.50" HMGs in the wings, the
20mm cannon were far more destructive... I don't think you'll be able to
single out any sinkings where the HMGs were decisive from all the
ones where the cannon did the vast majority of the damage :-/
> That seemed to do RATHER well at riddling them with holes and otherwise
> making life horrible for the Axis crews.
Well, yes. HE shells are quite good at blowing large holes in things. That
doesn't say very much about the non-explosive 0.50" HMG bullets,
unfortunately.
> The Mosquitos of RAF Bomber and Coastal Commands also did rather well
> against German E Boats.
The Mossies were armed with 20mm Hispanos and .303"-cal MGs, not 0.50"
HMGs.
In addition to this, there is a wee bit of difference in trajectory between a
projectile fired more or less horisontally from one boat to another (which was
the original premise of this thread) and a projectile fired at a
downwards slant from an aircraft to a boat. The air-launched projectile
doesn't need to go nearly as far through water to reach the underwater part of
the target's hull (in fact, if it goes through the deck it can penetrate the
hull from the inside, only entering the water *after* it has holed the hull).
All in all, I don't think that these examples of aircraft armaments are very
useful for discussing how far HMG bullets can travel through water and
still be dangerous to a target boat :-/
Ah well. I'll stop discussing this now, before I write something I'm not
allowed to :-(
Regards,