15 replies to this topic

[CFC Conky]

I know we won’t get it (50mm chain gun), but a guy can dream...


https://m.youtube.co...h?v=U0prcaXEwKU

Edited by CFC Conky, 02 November 2019 - 04:12 PM.

[Mister Maf]

I would think ultra autocannons or massed AC2s to be a pretty close analogue.

[R79TCom1 Night Lanner]

That's just a normal or, depending on the rate of fire, it's at best an ultra autocannon as described in Lore. I believe 50mm is an AC2 or AC5.

https://www.sarna.net/wiki/Autocannon

Edited by R79TCom1 Night Lanner, 02 November 2019 - 07:10 PM.

[FRAGTAST1C]

We can't have that gun in Battletech universe without them jamming. So....

[Dee Eight]

If you own the battletech technology hardcover manual from a decade or so ago, it explains that the classes of auto cannons are just that... classes. They don't necessarily mean that every manufacturer does their respective product the same way to achieve the same resulting performance. One brand's AC/2 might be a single shot 50mm while another's might be a stream of 20mm shells. We can see real world examples of that already in naval gun systems. For most world naval powers there's currently six calibers of guns used as the primary gun armament on frigates and destroyers. These are 57mm, 76mm, 100mm, 113mm, 127mm and 130mm. Now the Bofors 57mm L/70 Mk2 as fitted to the Canadian Halifax class frigates for example has a rate of fire of 220 rounds per minute, and each shell weighs about 2.4kg. The OTO-Melara 76mm L/62 Compact as fitted to the American Oliver Hazard Perry class frigates has a rate of fire if 85 rounds per minute and each shell weighs 6.3 kg. Now you do the math and the 57mm can fire off 528kg of shells in a minute and the 76mm can fire off 535.5 kg, which is so close that in battletech terms they'd both be considered the same class of Auto Cannon.

Edited by Dee Eight, 02 November 2019 - 09:01 PM.

[R79TCom1 Night Lanner]

Exactly, see my link above. Sarna goes into that as well for the people who aren't so lucky to have the old books.

[Dee Eight]

Yep, and to anyone who ever asks why the effective range is so short for these massive caliber auto cannons its because the armor plating used on battlemechs is so tough. Effective range is just that... EFFECTIVE at defeating the target. Take a mech with an ac/20 and advanced zoom into testing grounds on say crimson or river and stand off at a distance beyond the range of the gun shooting at regular map destructible objects. You can destroy the stuff well beyond the range at which you can damage a battlemech.

[R79TCom1 Night Lanner]

Dee Eight, on 03 November 2019 - 10:22 AM, said:

Yep, and to anyone who ever asks why the effective range is so short for these massive caliber auto cannons its because the armor plating used on battlemechs is so tough. Effective range is just that... EFFECTIVE at defeating the target. Take a mech with an ac/20 and advanced zoom into testing grounds on say crimson or river and stand off at a distance beyond the range of the gun shooting at regular map destructible objects. You can destroy the stuff well beyond the range at which you can damage a battlemech.

Yeah, that's the handwavium the BattleTech creators used to explain the short ranges: super advanced future armor and basic electronic countermeasures built into all BattleMechs. The real reason is that they didn't want the play area to take up a whole living room.

[Burning2nd]

why would we want projectile weapons.. when we have DEW?

[Y E O N N E]

Dee Eight, on 03 November 2019 - 10:22 AM, said:

Yep, and to anyone who ever asks why the effective range is so short for these massive caliber auto cannons its because the armor plating used on battlemechs is so tough. Effective range is just that... EFFECTIVE at defeating the target. Take a mech with an ac/20 and advanced zoom into testing grounds on say crimson or river and stand off at a distance beyond the range of the gun shooting at regular map destructible objects. You can destroy the stuff well beyond the range at which you can damage a battlemech.

The ranges are also the way they are as an abstraction of recoil. The effective range of an AC/20 is so short because the recoil of the projectiles that make up the 20-points of damage are not expected to all connect if fired at the same distance as, say, an AC/5, so they truncate the range brackets.

[Nesutizale]

Still weapon ranges in BT are way shorter then todays tanks, that is if I recall correctly that a hex is about 30m in diameter.
An AC2 would then have a range of 480m (16hex x 30m) compared to the 2500 - 5000m combat range of todays tank guns.
Even some values of random autocannons today have an effective range of 1600m.
In BT that would be ~54 to ~166 hexes. That would require quite some space to play on.

Sure in a computer game you could increase ranges but then it would be more like a flight simulation where you fire at targets you can't even see and where most of the targeting would be handled by the onboard computer then by you.
Also that would make the performance differance of old IS computers compared to the clans special targeting computers much more belivable.

It would also make missiles much more interesting and differantiate them from the direct fireing guns.
Mechs, even assaults have quite a high speed and can turn pretty fast, so when firing a shot at 5000m, the target might be able to evade it more easly while a missile can have a limited correction. Would still spread like hell and I imagne a LRM 20 to be more like an Stalin organ / artillerie.

In short combat would be much different that way. So I think the decission to have shorter effective ranges is both practical in nature as well as more interesting for most people.
Its pretty much the same reason why World of Tanks or World of Warships have scaled down ranges and speed up units.

[LordNothing]

i like the machine gun = gau-8, ac2 = howitzer analogy. but to be fair guns in battletech/mechwarrior never made much sense. like the inversely proportional range to calibur relationship which is the complete opposite of how guns work in the real world.

jam characteristics are another area where bt is completely wrong. something that jams as much as a uac20 would never be used by any active military on grounds of being completely unreliable. things that cause jams like poor maintenance and barrel overheating are replaced by a completely arbitrary rng. jamming should be more deterministic with length of barrage and weapon damage being what decides if the gun jams or not.

i dont think any game has implemented the gatling gun correctly. its almost always some kind of "charging" effect, when a real gatling is going to have its ammo feed mechanically synced to the barrel rotation, every time a barrel passes the firing position it will go off (unless you are out of ammo) and spinup occurs much faster irl. the notion of a sustained fire ballistic is also somewhat bogus as even your run of the mill gatling gun will fire in short bursts. racs are almost always used in a facetanking role but that would never happen irl.

of course there are technical issues. rapid fire weapons in particular would create so many objects in such a short period of time that no game engine could collision detect every bullet. multiplayer games add to it because you also have a limit to the number of updates you can transmit over the network. you can either use an abstraction of a bullet stream (hit scan for example), or do fewer more damaging rounds, and mwo does both.

Edited by LordNothing, 04 November 2019 - 05:46 AM.

[LordNothing]

Dee Eight, on 03 November 2019 - 10:22 AM, said:

Yep, and to anyone who ever asks why the effective range is so short for these massive caliber auto cannons its because the armor plating used on battlemechs is so tough. Effective range is just that... EFFECTIVE at defeating the target. Take a mech with an ac/20 and advanced zoom into testing grounds on say crimson or river and stand off at a distance beyond the range of the gun shooting at regular map destructible objects. You can destroy the stuff well beyond the range at which you can damage a battlemech.

projectiles really dont lose energy that fast. especially a 142kg ac20 round. sure you lose energy due to aerodynamic drag, but were talking high mass high velocity projectiles. and guns do kind of have an economy of scale working in their favor, a bullet doubles in size but its mass goes up 8x, so the bigger the gun the less energy you lose to drag in relation to the energy of the projectile. i think energy is 0.5*m*v*v or something like that, so our ac20 round is like 30 million joules.

[thievingmagpi]

I always saw the AC20 in MWO as just a big heavy HE round. No actual AP but gets by cracking armour because it's so damned big. In my mind (because BT Lore rarely makes any kind of sense) it was either improvised or adopted from a bunker buster style round sort of like a Sturmtiger orChurchill AVRE (380mm and 290mm IIRC). Hence the low velocity and firing arc. That's always made more sense to me in my head than whatever the BT Lore nonsense is.

I generally picture mechs being about 1/5th of the size they are depicted as in most lore, so there's that too.

Edited by thievingmagpi, 04 November 2019 - 08:30 AM.

[Y E O N N E]

TBQH, nothing about BT armor makes sense. An ablative might help you diffuse the energy of a squash head round on a square hit, but it's not going to do jack against a HEAT round at the same angle. Even at an oblique angle, the energy is far too concentrated in both size and time domains. For similar reasons, the ablative nature also wouldn't help much against a PPC round or even a laser.

Basically, space magic.

[KGeddon]

Dee Eight, on 03 November 2019 - 10:22 AM, said:

Yep, and to anyone who ever asks why the effective range is so short for these massive caliber auto cannons its because the armor plating used on battlemechs is so tough. Effective range is just that... EFFECTIVE at defeating the target. Take a mech with an ac/20 and advanced zoom into testing grounds on say crimson or river and stand off at a distance beyond the range of the gun shooting at regular map destructible objects. You can destroy the stuff well beyond the range at which you can damage a battlemech.

It's probably more of reduced propellant charges matched with poor stabilization for the extreme conditions of giant robot vs giant robot combat.