New Combat rules proposal

[Silverhawk]

If you SERIOUSLY want to have a "build your own" system for gun design spanning an incredibly wide swath of tech levels ... there is a singular go to source that will supply ALL of your gunbuilding needs.

Guns! Guns! Guns! published by BTRC (the Blacksburg Tactical Research Center).
I have an original edition version published in the 90s on my shelf, and that book taught me more about guns (how they work, how they are made, etc.) than almost anything else in the fiction and non-fiction book markets (s'truth!). 3G was simply THAT USEFUL for thinking about how to model guns and their performance.

I even have an electrical engineering friend of mine who built sonars for the USN ask me ... "what's the cartridge equivalent to electrical capacitors capable of holding 1200 joules? I need to explain the potential hazards of a short circuit in the wrong location to some students I'm training."

So I went to a handy copy of Guns! Guns! Guns! on the shelf, consulted the tables in the back for standard ammo, found the nearest match and replied ... "a 12 gauge shotgun shell" ... to which my friend thanked me profusely and was able to tell their EE students that if they were careless around the board and it blew up in their faces, just ONE of the capacitors (and there was more than one on the board!) would explode with the explosive energy of a 12 gauge shotgun shell, at close range ... and there would be fragmentation effects involved in the rapid unscheduled disassembly involved (and a bad day would be had).

Apparently the warning focused the attention of those students EXTREMELY EFFECTIVELY on the potential hazards of carelessness around having that much potential energy stored in the capacitors on that specific circuit board design ... because I never heard of anyone shorting something out and having the capacitors blow up in their faces, ruining everyone's day, after the safety briefing had been given. For some reason, everyone who worked with that circuit board had the requisite amount of RESPECT for what they were handling (not quite sure why though, since other boards would sometimes explode parts from time to time, but that's the EE defense contracting world for you).



So consider this a major shout out on the value of Guns! Guns! Guns! by BTRC beyond the book's application to "mere" gaming situations.

If you don't have a copy ... you want one ... even if you didn't know it yet.

I picked ups copy back in the day. Since it allowed designs for multiple systems including Traveller, I was looking at doing alien weapons that were really 'alien'.

 

[Spinward Flow]

We have to assume that the bullet composition is designed to better expand within the target vs just punch right through.

Could do something as simple as a carefully controlled mix of soft and hard steel so the projectile isn't a single homogenous bit of metallurgy. Kind of like how shaped charge warheads aren't a single homegenous lump of explosives (with double shaped charge warheads emphasizing the point even more).

Additionally, you're usually going to be looking at needing to "punch through" what is effectively exoskeleton armor (battledress) at gauss rifle tech levels before getting into the "squishy bits" inside with the projectiles for anti-personnel weapon applications. Anti-materiel weapon applications are just maximum penetration for "putting holes in things" that ruin machinery.

 

[Blue Ghost]

Here's what I found;

Guns! Guns! Guns!

BTRC - Blacksburg Tactical Research Center

www.btrc.net

 

[Spinward Flow]

Here's what I found;

Guns! Guns! Guns!

BTRC - Blacksburg Tactical Research Center

www.btrc.net

That looks like the cover I have of the book on my shelf (from back in the 90s).
The version of of Guns! Guns! Guns! on the DriveThruRPG site appears to be a later edition (3rd edition?) with a lot of layout formatting and art updates to the book.

 

[infojunky]

That looks like the cover I have of the book on my shelf (from back in the 90s).
The version of of Guns! Guns! Guns! on the DriveThruRPG site appears to be a later edition (3rd edition?) with a lot of layout formatting and art updates to the book.

Looks like the edition I have with the spreadsheets, late 90s or so. Used it with both TNE and T4. Note Porter did the vehicles and tech book for T4 as well.

 

[aramis]

That looks like the cover I have of the book on my shelf (from back in the 90s).
The version of of Guns! Guns! Guns! on the DriveThruRPG site appears to be a later edition (3rd edition?) with a lot of layout formatting and art updates to the book.

Yep. but if you ask him nicely, Greg might send you the MegaTraveller conversion. ISTR the T4 conversions are in the PDF.

 

[Condottiere]

What's the supposed muzzle velocity of a gauss rifle, fifteen hundred metres per second?

Engagement range three hundred metres, human width plus armour half to one metre?

One fifth of a second to target, fifteenth hundredth of a second, adjust for deceleration, through it.

While the slug has been described needle like, which I think is more like a fat nail, once it penetrates the body armour, not much stopping it slicing right through flesh, with bone solid enough to slow it down.

Or maybe it's a tack, since it's listed as being four grammes in weight; discarding sabot would certainly make it more needle like and naturally, increase it's velocity.

 

[whartung]

The GR round is a hollow point. Once it starts to enter the body, it begins to expand. Obviously it has to expand quickly enough to transfer some of the energy to the target.

Also, when the bullet starts to deflect, it also rapidly destabilizes, which causes it to tumble, and possibly fragment, tossing the jacket off as the core goes about it merry way.

In the shooting parlance, its called "keyhole", rather than seeing a nice round hole in a paper target, you see an elongated one, like a keyhole, showing that the bullet entered more "sideways" on nose on.

But this all happens within the target. Now instead of a 4mm dart flying through soft tissue like an arrow, you have an inch long bullet pitching and yawing. The hollow points sudden expansion can help induce this, much like seeing a bicycle hit something and the rider pitches over the handle bar. The bullet is borderline stable enough in flight, it doesn't take much to mess up it's happy path.

 

[mike wightman]

Hollow point is useless against TL12+ body armour, the GR round is good vs armour so it can't be hollow point.

 

[McPerth]

According LBB4:

Gauss Rifle: (...) the gauss rifle generates an electromagnetic field along the length of the barrel which accelerates a 4 mm, 4 gram needle bullet to velocities of 1500 meters per second. The round itself consists of a dense armor piercing core surrounded by a softer metal covering, ending in a hollow point, giving the round both high stopping power and a good armor piercing capability.

Being a nearly ignorant in the issue (at least compared with others in this board) I always understood that a bullet that deformes upon impact would always be a poor armor piercing one, while one that not would be "less damaging", but a better armor piercing one...

Does it sound too stupid to think about "foldable" spanding "needles"? Those would fole while passing through the armor, but expand again when its sourrounderings are softer, and on a spinning bullet they could be quite damaging...

 

[Condottiere]

1. Should be easier than trying to figure out how a jump drive works.

2. Aerodynamics - would that have an effect on the shape of the bullet, or will it be a traditional spitzer?

3. Armour-piercing, capped, ballistic capped, with a steel jacket, and maybe a lead centre.

4. Four grammes may be the default steel jacketed bullet.

5. I'm not sure how creating a hollow point on the tip is going to effect aerodynamics.

 

[Condottiere]

Lever action energizes onboard battery.

 

[whartung]

Hollow point is useless against TL12+ body armour, the GR round is good vs armour so it can't be hollow point.

Nonetheless, the GR does high damage and has really good penetration. It says it's a HP and AP. At TL 12, apparently they've reconciled the two to work in a single round. Let's hear it for those Imperial material scientists!

(Anyone have any idea how to read the weapons table in Mercenary when there are two values for a column?)

 

[Spinward Flow]

Let's hear it for those Imperial material scientists!

Shape-memory alloys ...

 

[mike wightman]

Which source says it is hollow point and armour piercing?

More likely the needle tumbles as it enters the body tissue and is designed to then fragment due to the stresses...

 

[McPerth]

Anything it is, it must be quick, as the bullet would cross the body in less than 0.0003 seconds...

Shape-memory alloys take a little more time, I'm afraid, and any effect the body might have on the bullet is likely to also be produced by the armor (e.g. I guess if the projectile will fragment on entering the body (remember in less than 0.0003 seconds) i guess it would also while hitting armor), so making it a poor armor-piercing round...

Of course, this is seen from TL8 perspective, not TL 12 one...

 

[whartung]

Which source says it is hollow point and armour piercing?

The round consists of a dense armor piercing core surrounded by a softer metal covering, ending in a hollow point, giving the round both high stopping power and a good armor piercing capability.

Book 4 p37 (and, boy, the OCR was just throwing darts on this sentence lol.)

 

[Spinward Flow]

Book 4 p37 (and, boy, the OCR was just throwing darts on this sentence lol.)

Let me guess ... those darts had 4mm cross sections, weighed 4 grams each, and the gunner was unskilled ...

How'd I do?

 

[Blue Ghost]

Well, it is all fiction. But like McPerth said, materials, in particular ferrous alloys, take time to move and bend. Maybe GR rounds are predominantly made of some other material but with some steel included.

 

[kilemall]

I’ll mention my CT Striker mod again, more for others not aware of it as I don’t think you value the granularity.

Two rolls once hit achieved, first roll is hit location and derives 1d for extremities 2d for center mass 3d for head, character gun skill increases placement for more damage. Second roll is for armor pen effects, can yield -3d to +3d. Explosive or blunt trauma can add 1d (usually paired with low pen like say a mace or lower pen HP rounds). Add up damage roll and apply.

Several reasons I went this way- differential armor like vest but open extremity/no helmet gets handled, daggers or handguns can do lethal damage against say an unprotected head or nothing against heavy suit armor, and a PGMP hit might be lucky and just hit a leg and not be an auto kill. An additional payoff is I generate which body part gets hit with what level of damage/stat and can describe the wound creating medical drama/tasks for the medic.

I really like Striker’s differentiation between say battle rifle, carbines and assault rifles. Should also mention the subtlety inherent in the original CT’s Dex mods, really gives a feel for easy to handle weapons vs ones with more of a kick. Real hard choices at times for best weapon to optimize with..