71 replies to this topic

[The6thMessenger]

Yeonne Greene, on 11 February 2017 - 01:00 PM, said:

Yeah. The fact that our AC/2 are firing as fast as a Gauss Rifle...they must be Light Gas guns or something, because that is truly impressive.

There's more to projectiles than just speed. AC2s could have been just really light projectiles flies fast. Gauss slugs could be really heavy AND flies fast.

[Y E O N N E]

The6thMessenger, on 11 February 2017 - 03:50 PM, said:

There's more to projectiles than just speed. AC2s could have been just really light projectiles flies fast. Gauss slugs could be really heavy AND flies fast.

It's not just the speed or mass at the speed. It's impressive simply because of the physics limitations of conventional propellants. As your projectile gets faster and further down the barrel, it starts outpacing the pressure head of the gas expanding behind it. To get around this using expansion, you basically have to neck down to a smaller bore to create a higher pressure ( P = F/A). Bullets sometimes do this with their casings, but you have to get even more dramatic for insane velocities (i.e. > 1,500 m/s). That's what the Light-gas gun does, in so many words.

[NighthawK1337]

Prosperity Park, on 11 February 2017 - 12:31 PM, said:

... there is a huge difference in firing mechanism between those two weapons...

A Gauss rifle uses electromagnets to pull and drag a magnetic slug down the barrel and sling it out. It's not particularly destructive to the barrel, and there is no glow or plasma.

A RailGun uses a a very, very powerful electric discharge to repel a conductive, but non-magnetic slug and push it forward down the barrel. This mechanism causes the rails to experience extreme electric discharges and plasma arcing which causes rapid barrel deterioration. It also burns the skin off the back of the slug.

A Railgun is a little bit more complicated. If it's using a sabot as the armature, the slug could be either, but if it's not using a sabot the slug has to be magnetic because it needs to induct a magnetic field so that it will be propelled forward. Either way, there has to be a magnetic part in the projectile.




Given that MWO Gauss Rifle also has a sabot (the stuff that goes to the side when you fire the gauss rifle), its projectile is comparable to a real life railgun.

The mechanism might be different but the end result is the same, a hyper velocity projectile weapon.

Edited by NighthawK1337, 11 February 2017 - 05:23 PM.

[Mister Glitchdragon]

Let's not spend too much time and energy on the physics. The GR shares a battlefield with 5-ton battle computers and "Long Range Missiles" with a 1k max range. The science in this fiction isn't that good to begin with.

As far as game play, the GR's range just got nerfed, its big, heavy, has a slow ROF on top of its awkward firing mechanic, lousy ammo/ton, and explodes when you look at it funny. I guess that's not enough for some people.

I'm sorry the OP got zapped by a good sniper and didn't get a "shoot here" arrow to fire back at. Along with no heat, ninja moves are one of the few advantages left for GR-users.

So no.

[Hit the Deck]

Yeonne Greene, on 11 February 2017 - 12:47 PM, said:

...
Those shards you are referring to would be called a "sabot", though I don't actually know why you would need one for a Gauss rifle. The projectile is ovoid, perhaps a rod, and it never touches the sides as it's suspended by both magnetic and aerodynamic forces. You need a sabot for conventional arms and rail guns because your smaller caliber projectile needs to make contact with the bore in order to be accelerated. For rail-guns in particular, you need it because the bore is typically of a different shape than the projectile.

Thanks for telling me about the name. I've heard sabot but I thought it was a type projectile.

As for the sabot itself, I imagine you'll still need some kind of casing for the projectile in real world application for various reasons, like what if what you accelerate is actually the sabot itself rather than the more complexly shaped and not necessarily ferrous projectile.

[Y E O N N E]

NighthawK1337, on 11 February 2017 - 05:22 PM, said:

A Railgun is a little bit more complicated. If it's using a sabot as the armature, the slug could be either, but if it's not using a sabot the slug has to be magnetic because it needs to induct a magnetic field so that it will be propelled forward. Either way, there has to be a magnetic part in the projectile.


Given that MWO Gauss Rifle also has a sabot (the stuff that goes to the side when you fire the gauss rifle), its projectile is comparable to a real life railgun.

The mechanism might be different but the end result is the same, a hyper velocity projectile weapon.

Nothing about a rail-gun requires anything to be naturally magnetic or even ferrous. It need merely conduct electricity well enough to generate a useful magnetic field when current passes through it (that whole right-hand rule thing).Rail-guns are brute-force weapons, it's all about current. Current gives you everything you need to make it fire except the initial push; most rail-gun projectiles are injected by compressed air or some other apparatus.

Gauss Rifles are fancier, using timed switches to cycle magnetic fields and foist a projectile to speed. Because it's relying on magnetic fields to act on something that isn't itself generating a substantial magnetic field (i.e. no current running through it like in a rail-gun), that projectile has to be ferrous. Or we have to dump enough energy through our coils to generate a magnetic field strong enough that it can act on non-ferrous objects to the same degree.

[LordNothing]

im actually going to call ares convention on this one. battletech seems to use the concepts of "civilized warfare". you know where you wore brightly colored uniforms and marched shoulder to shoulder to another army's line, and depending on era, charge with swords or fire 3 rounds, fix bayonets and charge. i always said its the main reason all weapons are limited to visual range engagements. you cant just jdam and chill like you do in the real world. so i would say that the ares convention requires all projectile weapons to have visible tracers, to keep things civilized.

also rule of cool. the gauss projectile looks rather disapointing after you put 15 tons of crit happy gun in your mech, just to get a pathetic looking projectile. give it a big bright orange tracer and make it look awesome.

The6thMessenger, on 11 February 2017 - 03:50 PM, said:

There's more to projectiles than just speed. AC2s could have been just really light projectiles flies fast. Gauss slugs could be really heavy AND flies fast.

lighter slugs loose momentum faster. and that makes them slower.

lets face it none of the ballistics in battletech make sense. big guns that should go many km barely go a few hundred meters, and hypersonic ac2s should be impossible. then on top of that different atmospheric conditions and gravity would greatly affect ballistic characteristics. a ballistics simulator mwo is not.

Edited by LordNothing, 11 February 2017 - 06:27 PM.

[Y E O N N E]

Hypersonic ballistics through means other than electromagnetic are most definitely not impossible.

[NighthawK1337]

Yeonne Greene, on 11 February 2017 - 05:47 PM, said:

Nothing about a rail-gun requires anything to be naturally magnetic or even ferrous. It need merely conduct electricity well enough to generate a useful magnetic field when current passes through it (that whole right-hand rule thing).Rail-guns are brute-force weapons, it's all about current. Current gives you everything you need to make it fire except the initial push; most rail-gun projectiles are injected by compressed air or some other apparatus. Gauss Rifles are fancier, using timed switches to cycle magnetic fields and foist a projectile to speed. Because it's relying on magnetic fields to act on something that isn't itself generating a substantial magnetic field (i.e. no current running through it like in a rail-gun), that projectile has to be ferrous. Or we have to dump enough energy through our coils to generate a magnetic field strong enough that it can act on non-ferrous objects to the same degree.

That is true, it doesn't have to be ferrous, It just have to conduct and turn into an electromagnet. Ferrous material isn't necessary because having magnetic remanence isn't a requirement.
My point was they both use Electromagnetism as a primary mechanism and there's magnetic fields interacting with the projectile either way, not just current like Prosperity Park said.
If the sabot is the one that conducts it will turn into an electromagnet like all current carrying conductors, the projectile doesn't have to interact with the magnetic field.

Getting sidetracked though,

Main idea is the projectile doesn't need to glow reality-wise since there's a sabot minimizing barrel friction, which isn't a big problem in Gauss in the first place compared to a Railgun in the video.

Yeonne Greene, on 11 February 2017 - 06:49 PM, said:

Hypersonic ballistics through means other than electromagnetic are most definitely not impossible.

Light gas gun comes to mind.

[Y E O N N E]

Quote

Light gas gun comes to mind.

I feel like chopped liver, I said that on page 1! And linked to it at the top of this page!

D:

Edited by Yeonne Greene, 11 February 2017 - 09:00 PM.

[Snowbluff]

Hit the Deck, on 11 February 2017 - 03:57 AM, said:

The nickel-ferrous melon ball doesn't fly fast enough that the friction between it and the air heats up the projectile so it glows.

The electromagnetic force is high enough that you just get flame when the round goes out.

Actually, the momentum of the gauss is ridiculous. I think we calculated with would flip a tank over...

[NighthawK1337]

Yeonne Greene, on 11 February 2017 - 08:59 PM, said:

I feel like chopped liver, I said that on page 1! And linked to it at the top of this page!

D:

oh,
I reread the whole thing, you're right, you did mention it and something about AC/2s being too fast.

Another person who knows his obscure experimental weapons? You sir have my respect.

Missed that one, I was focused with Prosperity Park's reply.

Snowbluff, on 11 February 2017 - 09:09 PM, said:

The electromagnetic force is high enough that you just get flame when the round goes out.

Actually, the momentum of the gauss is ridiculous. I think we calculated with would flip a tank over...

I posted a real life test video of that and found that it isn't enough to get a flame while flying. The flames there were from the barrel getting superheated.

Edited by NighthawK1337, 11 February 2017 - 09:48 PM.

[Tripzter]

Personally i'd like to see a ripple effect of some kind instead.

[Snowbluff]

NighthawK1337, on 11 February 2017 - 09:41 PM, said:

I posted a real life test video of that and found that it isn't enough to get a flame while flying. The flames there were from the barrel getting superheated.

The MWO gauss is significantly more energetic than modern systems. The speeds aren't terribly incredible, but the rounds are 15th of a ton rather and a couple of kg.

[NighthawK1337]

Tripzter, on 11 February 2017 - 10:09 PM, said:

Personally i'd like to see a ripple effect of some kind instead.

Hell yeah, this would visually make it closer to the oldermech warrior games.

Snowbluff, on 11 February 2017 - 10:30 PM, said:

The MWO gauss is significantly more energetic than modern systems. The speeds aren't terribly incredible, but the rounds are 15th of a ton rather and a couple of kg.

That may be so but their speed is comparable. Given that the friction comes from how fast the projectile is sliding against the air, there won't be flames either way. The best we can do is the air distortion, bigger flash, and bigger impact effects.

[Clanner Scum]

I want the gauss impact sound effects from mechwarrior 4. So jarring when you got slamed by light gauss from 2000m away.

[Snowbluff]

NighthawK1337, on 11 February 2017 - 10:34 PM, said:

That may be so but their speed is comparable. Given that the friction comes from how fast the projectile is sliding against the air, there won't be flames either way. The best we can do is the air distortion, bigger flash, and bigger impact effects.

The larger projectile has more drag. That drag causes losses as heat.

[Tripzter]

Snowbluff, on 11 February 2017 - 10:47 PM, said:

The larger projectile has more drag. That drag causes losses as heat.

All depends on teh density assuming both shells are teh same shape.=. More dense projectile will hold its velocity longer.

Edited by Tripzter, 11 February 2017 - 10:53 PM.

[Y E O N N E]

Snowbluff, on 11 February 2017 - 10:47 PM, said:

The larger projectile has more drag. That drag causes losses as heat.

Not necessarily true. Geometry matters. A lot.

[LordNothing]

Yeonne Greene, on 11 February 2017 - 06:49 PM, said:

Hypersonic ballistics through means other than electromagnetic are most definitely not impossible.

impossible, no (i really should have used a better word). but not from a 5/6 ton weapons system? i know light gas guns can get that fast, but the barrel length would be rather impractical as a weapons system.

Yeonne Greene, on 11 February 2017 - 10:56 PM, said:

Not necessarily true. Geometry matters. A lot.

the important numbers are cross sectional area, and velocity (drag = 0.5 * pressure * velocity^2 * area * dragCoefficient). drag goes up with both. so you are going to see faster rounds pretty much looking like darts and fired using a sabot, shock cones and all.

Edited by LordNothing, 11 February 2017 - 11:24 PM.