Weird Gun Guestion III: "Thunderzap Ammunition"

[Bathawk]

Hey all, this is my third question asking about unique weapons as I continue to translate characters into Gurps (if anyone is interested, I'm currently going through Hero Games "Justice, Not Law)

One character has a "Desert Eagle .50 with Thunderzap Ammunition"...Thunderzap? sounds made up, but sure enough, a google search found that it's a thing....anyone give me more info on what this is, and how it would translate to Gurps?

[Fred Brackin]

I never heard of it before but assuming the first thing Google came up was accurate it would fail the FBI handgun bullet test. The FBI wants 12" of penetration of ballistics gelatin to simulate a torso wound with both entry and exit holes to maximize bleeding. The Thunderzap achieved only 5".

We now come to the very influential name of Dr Marvin Fackler and his wounds Ballistics Laboratory. Those huge holes the Thunderzap made in test mediums would be only temporary in living flesh which is elastic. Fackler deprecates temporary wound cavities and believes only bleeding is of permanent effect.

I will credit the Thunderzap people for confusing several issues by getting very high velocities out of handguns with very light ammo. It could be argued that they had turned a "magic corner" to get previously unknown effects from hydrostatic shock.....if it weren't for rifle bullets at the same velocities or higher with bullets that break up on impact and whose effects have been thoroughly studied.

This leaves you with Gurps stats that boil down to "Doesn't work as advertised". Maybe half damage or less with an armor divisor of worse than doubling DR it hits. Maybe something like 5x DR.

If it did anything in Gurps it might double the 1 second "Shock" penalty from iots' wounds but even that would be guess work.

[Anthony]

If you're translating from Hero -- real-world stats don't matter. Just look at its game stats. Or just make up numbers. I'm sure it was picked on 'sounds kewl' as opposed to any particular interest in realism.

[Bathawk]

Originally Posted by Fred Brackin

I never heard of it before but assuming the first thing Google came up was accurate it would fail the FBI handgun bullet test. The FBI wants 12" of penetration of ballistics gelatin to simulate a torso wound with both entry and exit holes to maximize bleeding. The Thunderzap achieved only 5".

We now come to the very influential name of Dr Marvin Fackler and his wounds Ballistics Laboratory. Those huge holes the Thunderzap made in test mediums would be only temporary in living flesh which is elastic. Fackler deprecates temporary wound cavities and believes only bleeding is of permanent effect.

I will credit the Thunderzap people for confusing several issues by getting very high velocities out of handguns with very light ammo. It could be argued that they had turned a "magic corner" to get previously unknown effects from hydrostatic shock.....if it weren't for rifle bullets at the same velocities or higher with bullets that break up on impact and whose effects have been thoroughly studied.

This leaves you with Gurps stats that boil down to "Doesn't work as advertised". Maybe half damage or less with an armor divisor of worse than doubling DR it hits. Maybe something like 5x DR.

If it did anything in Gurps it might double the 1 second "Shock" penalty from iots' wounds but even that would be guess work.

What is "Hydrostatic shock"? Saw that on a couple of forums. They seemed to imply that in kills your range but does extra damage in flesh, but shatter against any kind of solid surface like a composite bullet?

[RyanW]

Originally Posted by Bathawk

What is "Hydrostatic shock"? Saw that on a couple of forums. They seemed to imply that in kills your range but does extra damage in flesh, but shatter against any kind of solid surface like a composite bullet?

Hydrostatic shock is a supposed method of injury with firearms, with the claim that a bullet striking the body generates a shockwave that can injure tissues away from the path of the bullet. It's proponents tend to favor rounds that transfer maximum energy to their target to maximize pressure waves, while it's detractors tend to favor rounds that retain velocity to maximize the likelihood of penetrating to vital organs and/or generating bleeding exit wounds (or that fragment, creating multiple injury paths).

[Varyon]

Originally Posted by Fred Brackin

This leaves you with Gurps stats that boil down to "Doesn't work as advertised". Maybe half damage or less with an armor divisor of worse than doubling DR it hits. Maybe something like 5x DR.

Frangible rounds, which this sounds like, canonically have a (0.5) armor divisor, although being light plastic it may well be appropriate to increase DR further, for (0.25) or even (0.2) as you suggest. I'd say something like half damage, +1 to piercing-class, AD (0.2), and reduce Range to something like 10/100 (pistols in HT look to typically have a Max around 10x their 1/2D, and the forum thread I found - probably the same one as you - indicated the bullet is so weak at 100 yards you could probably catch it in your hand; 7/70 might be more appropriate, honestly, but I decided to give it a bit of a chance). Note also that .50 BMG were apparently experimental rounds, but .50 AE never existed (but could in an alternate history where TZ rounds weren't discontinued).

EDIT: Come to think of it, I believe I've seen a very similar round, albeit sized for a shotgun, in a Taofledermaus video. I might see if I can dig that up later.

[Pursuivant]

Originally Posted by Bathawk

What is "Hydrostatic shock"? Saw that on a couple of forums. They seemed to imply that in kills your range but does extra damage in flesh, but shatter against any kind of solid surface like a composite bullet?

Basic info here.

It's probably B.S., but since there are many different types of tissue in the human body and many types of bullets it might be true in some cases.

The original hypothesis came from a WW2 combat surgeon, who probably saw lots of injuries from high velocity bullets. Counter evidence came from studies of Vietnam War injuries and actually isn't as conclusive as originally claimed.

There was a big debate over it in the 1980s and 1990s and for a time lots of people thought that it was a real killer. Better technology then showed that many effects attributed to hydrostatic shock were actually due to bullet tumbling or fragmentation. Ballistic gelatin was invented to disprove hydrostatic shock/prove bullet tumbling.

In GURPS terms, any special effects from hydrostatic shock (if it exists) can be modeled as a higher than averaged damage dice roll and/or a failed roll to avoid Crippling.

[Donny Brook]

Hydrostatic shock results from the energy transfer from the bullet to the target. Bullets that penetrate and continue after that (e.g. FMJ) have retained some of their kinetic energy, whereas bullets that stop in the target (e.g. hollowpoint) have transfered all their energy to the target.

The difference in effect can most readily be observed in targets that are closed containers of a fluid, which can tend to explode dramatically with high energy transfer.

[mburr0003]

Originally Posted by Donny Brook

The difference in effect can most readily be observed in targets that are closed containers of a fluid, which can tend to explode dramatically with high energy transfer.

I've always wanted to see how ballistic gelatin acted in a closed container*... does it model the "hydrostatic shock" or does a medium closer to human flesh contain the shock and not explode like water in a one gallon jug (anyone who expects a human body to react like a plastic one galloon jug needs to re-examine their biases).

Also, larger vessels tend to contain the shock, but it's unsure if that's due to the vessel being stronger than flimsy milk jugs (even one gallon metal canisters tend to rupture), or if it's due to the larger volume of water absorbing the shock better. Probably both.


* Or a true test, a ballistic body molded on a skeleton with pressure patches throug out to show how much pressure is transferred at different distances in the body... but those wold be very expensive tests. Maybe if I hit that lotto hard enough.

[Ulzgoroth]

Originally Posted by mburr0003

I've always wanted to see how ballistic gelatin acted in a closed container*... does it model the "hydrostatic shock" or does a medium closer to human flesh contain the shock and not explode like water in a one gallon jug (anyone who expects a human body to react like a plastic one galloon jug needs to re-examine their biases).

Also, larger vessels tend to contain the shock, but it's unsure if that's due to the vessel being stronger than flimsy milk jugs (even one gallon metal canisters tend to rupture), or if it's due to the larger volume of water absorbing the shock better. Probably both.


* Or a true test, a ballistic body molded on a skeleton with pressure patches throug out to show how much pressure is transferred at different distances in the body... but those wold be very expensive tests. Maybe if I hit that lotto hard enough.

My impression is that ballistic gelatin very visibly displays shockwave deformation if you watch it getting shot with a high-speed camera...and it then snaps back with negligible lasting effect outside the bullet track.

However, if you stuck it in a small, brittle container I wouldn't be surprised if the gelatin blew out the walls nearly as well as plain water does...and then the gelatin itself kept sitting there with broken plastic hanging off it.


It's not the water that's getting hurt in that demonstration, after all.