Autocannon propellents

[greatsarcasmo]

Do we know what kind of magic stuff hurtles AC shells out at hyper-velocities? The Demolisher write-up in 3026 said it used "...a popular propellant system, that mixes two chemicals in suspension to propel a stream of huge shells at the luckless target."  Has this ever been talked about more in-depth?  And popular doesn't mean only--have any other methods been brought to light?  maybe a "super gunpowder" of some sort? 
Finally do AC shells look like what we are used to in a modern sense? a brass case filled with propellant and a shell?

[Arkansas Warrior]

NACs apparent use nuclear blasts.  I take it normal ACs are a little less extreme, but they're still pretty well beyond anything we have today, I think.

[Demon55]

Fiat.

[ShadowRaven]

monkies with croquet mallets.

Seriosuly, there are a number of chemicals that produce wonderful explosions when mixed. Sodium and Hydrochloric acid springs to mind. It's really hard to guess what else might be developed to make explosions

[Taurevanime]

I kind of doubt that they would use brass casings stills, a lighter and stronger material would allow you to carry more shells, and better heat conductive properties will keep the system cooler. Though I personally wouldn't be surprised if they used combustible bag charges, but that would be the caseless ammunition...
As to what propellant is used it would also be some future material, my money would be on it being a solid material most certainly due to the higher energy potential for size you get with that. But as to combining two chemicals together to fire projectiles? If you consider plasma a chemical than I can imagine it being plasma ignited propellants, an idea that has been floating around for a while now as the next step in tank armament, since rail guns would require nuclear powerplants for now.

That reminds me, are there still rules for caseless ammo, or has that been dropped?

[greatsarcasmo]

I knew it wasn't caseless, at least as it was presented in the Tactical Handbook.  I meant more the "look" of present-day brass shells if not the material. 

[Bren]

Tactical Operations has the rules for caseless.

[PeripheryPirate]

TechManual makes no mention of the propellant, and that would probably be the best place for it.

[rlbell]

Do we know what kind of magic stuff hurtles AC shells out at hyper-velocities? The Demolisher write-up in 3026 said it used "...a popular propellant system, that mixes two chemicals in suspension to propel a stream of huge shells at the luckless target."  Has this ever been talked about more in-depth?  And popular doesn't mean only--have any other methods been brought to light?  maybe a "super gunpowder" of some sort? 
Finally do AC shells look like what we are used to in a modern sense? a brass case filled with propellant and a shell?

Electro-thermal chemical propellants are a good guess.  By controlling the rate of plasma production, it is possible to limit the initial pressure spike and then, as the projectile travels along the guntube, match the pressure to what the tube will bear.  While this will waste alot of energy, it will increase the muzzle energy to the maximum that the gun can contain.

[LastChanceCav]

That might be a good explanation as it could be related to the arming/jamming issues described for UACs.

Cheers,
LCC

[cray]

Fiat.

Seconded.

The Demolisher's fluff was written before the writers apparently noted AT1 ranges (which were crazy long, about 6500km/hex) and turn lengths.

[SteelRaven]

Well, the Fluff about modern Tank rounds doing no damage to the first mech makes a little more sense now. I'll just say they upped MG a similar way.

[PeripheryPirate]

Well, the Fluff about modern Tank rounds doing no damage to the first mech makes a little more sense now. I'll just say they upped MG a similar way.

That's not a problem with the propellant of a modern round; it's the crazy-awesomeness of the 'Mech's armor.

[cray]

That's not a problem with the propellant of a modern round; it's the crazy-awesomeness of the 'Mech's armor.

Well, yes, it is a problem with the propellant of the modern round. BT autocannons fling projectiles at least 5 times as fast as tank guns. That makes a huge difference in damage that will not alter regardless of what it's hitting.

[Kit deSummersville]

Sodium bicarbonate and acetic acid.

[greatsarcasmo]

Sodium bicarbonate and acetic acid.

Vol-cannons?

[Kit deSummersville]

Vol-cannons?

Only if red dye is added.

[ShadowRaven]

Diet Pepsi and Mentos

[Kit deSummersville]

Diet Pepsi and Mentos

Whoa, I didn't think we were going into HVAC territory.  ;)

[ShadowRaven]

well the fluff did mention two popular chemicals

[Orin J.]

really, REALLY strong gnomes..... :D

[Schottenjaeger]

really, REALLY strong gnomes..... :D

You mix that, all you get is broken furniture and more gnomes.

[DevianID]

On a silly note, if we HAD to accept the deep space range as the correct range (I dont) then what about antimatter?  In the real world, we have been producing antimatter for a while, its just expensive.  But if you really need a big kick for a little weight, antimatter has 100% energy conversion!

[Kit deSummersville]

Well, real world anti-matter exists for nanoseconds at a time. Containment is rather difficult.

[DevianID]

Not 100% true.  Containment is difficult, but not impossible, and I figure since they nailed the fusion reactor, which we can only maintain for a scant few moments, then antimatter should be about the same, seeing as we use antimatter much more frequently in the real world than we do fusion engines.  Plus, I would rather use antimatter than garden gnomes.

[rlbell]

On a silly note, if we HAD to accept the deep space range as the correct range (I dont) then what about antimatter?  In the real world, we have been producing antimatter for a while, its just expensive.  But if you really need a big kick for a little weight, antimatter has 100% energy conversion!

The difficulty with antimatter/matter annihilation is that, while the energy conversion is 100%, the efficiency for collecting that energy is much smaller.  Annihilation energies are released as hard gammas.  While gamma rays are much more interactive than neutrinos, something as small as a McKenna will lose a significant portion of the gammas to outer space and much of the intervening structure will be irradiated.  The other difficulties are producing the antimatter and storing it.  Each kilogram of antimatter requires fusing about 250 kilograms of hydrogen, even more if there are any losses in converting the antimatter.  Conversion innefficiencies that are radiated as heat will be really bad, considering the energies involved; unless, production rates are really low, like at CERN (which might produce thousands of antiprotons a second).  Storing antimatter is as difficult as storing hydrogen plasma with the added problem of annihilation reactions with the walls of the containment and any stray atoms.

CERN manages most of the difficulties of storing antimatter by only keeping 10^-14 grams of the stuff (billions of antiprotons) handy, at any given time.

[Kit deSummersville]

Not 100% true. 

Then provide a citation for anyone containing anti-matter for more than the nanosecond range.

[rlbell]

Then provide a citation for anyone containing anti-matter for more than the nanosecond range.

CERN has stored antiprotons for days, possibly months, as it collected enough for their experiments.  However, it is not enough antimatter for you to really notice if you could somehow, accidentally swallow all of it.  The storage rings are similar to synchrotrons and use magnetic fields to keep the antimatter from encountering any matter..  According to wikipedia, CERN loses 99.9% of the antiprotons as they are cooled enough to be stored.  As of 2006, the cost of antimatter is $25 billion dollars a gram.  CERN's storage rings have never contained more than millions of anti-protons

[verybad]

Sodium bicarbonate and acetic acid.

Damn it! I was gonna say Vinegar and baking powder! The only thing left to use is a really big rubber band.

The use of nuclear explosions in NACs doesn't really compute for me, because how then do you explain the performance of somethign like an AC-2, which has longer range than an NAC-40? Pr that NACs typically have shorter ranges than Naval Gauss weapons?

I thing they just use plain old fashioned black gunpower.

[Kit deSummersville]

I was hoping for a citation, preferably something peer reviewed, not some random stuff off the web.

Like this Nature article, where they've managed to trap anti-matter for a whole 170 milliseconds.

You might also want to read your wikipedia entries. The 'cost' of antimatter was the price to produce it, it isn't available as a market commodity. Don't try to pull the wool over the eyes of guy who works in the biggest anti-matter field out there.