33 replies to this topic

[The Boneshaman]

dakka
the problem i have found with this guys info on the ac20 being 203mm and has so much force it will knock a mech backwards is this. every thing in lore i have read has said the ac20 is any where between a 25mm and 203mm. all books i have read have said the mech/ vehical with an as 20 is fireing a 120 mm cannon with a stream of bullets. i never had to roll piolting skill for fireing 1 or more ac20's only when fireing a heavy gauss or taking 20+ damage. you roll pioliting skill +1 for every 20 points of damage you take. one good book on this is Threads_of_Ambition. on one page it mentioned a Hetzer fireing a 120mm ac. and in a Dark Age novle (dont remember what one.) it mentioned a hunchback with a sholder mounted ac vommiting a stream of 120 mm depleted uranium rounds at the main characters mech. unless this is a rule change from TW books. ac 20 knocking a mech beack whene fireing is wrong. but if i am wrong pleas show me the info. hear is also some sarna info on ac 20s http://www.sarna.net...i/Autocannon/20

[B E E L Z E B U B]

Koniving, on 10 November 2013 - 06:50 PM, said:

I like autocannons, but I don't especially like how they are in MWO. Has anyone been reading up on the lore? Most ACs fire in bursts (by burning through entire magazines called cassettes) or chain fed MG-style, fully automatic. Of course, most ACs are rated by damage per burst or by damage per unit of time (in TT it'd be 10 seconds, in MWO's case this unit of time is 4 seconds for AC/20, 2.5 seconds for AC/10, 1.5 seconds for AC/5 and 0.52 seconds for AC/2).

Can you imagine this much dakka for 1 AC/20? That's the Crusher Super Heavy Cannon (a semi-common AC/20). The Atlas's Deathgiver pumps out 15 shots (undefined as to whether cassette[Burst] or chain[MG] based). The Hunchback's got a 5 shot. The Chemjet Gun is a 4 shot. The Hunchback IIC's twin UAC/20s are both 6 shots (with ultra churning out 12 shots per cannon) in an MG-style.

*Salivates about dakka now.*


Time between shots is included. 20 damage upon impact, 4 seconds to fire again. Thus 5 DPS. The vid above on the link "Dakka" demonstrates "5 DPS" in 4 different ways. If the AC/20 took 5 seconds to reload, it would be 4 DPS.

DPS is a rating of how much damage is done divided by how many seconds it takes to do it again.

I see, thank you buddy.

[Koniving]

Specifically, Boneshaman, at the time I did that video I had my info wrong. I based it on an image that introduced me to the concept and a single online book. In the book they mounted the Cauldron Born's UAC/20 on an Atlas as an experiment. If you notice I also said the Chemjet Gun is a 4 shot but demonstrated it as a 3 shot. Also it turned out to be a fan-written book.

That aside, tabletop doesn't account for any weapon variants. It doesn't account for stream fire (constant fire) spread. It doesn't account for burst fire, recoil, etc. However lore specifically mentions that recoil is one of several reasons for range limits when they otherwise wouldn't make sense.

Far as whether a 203mm would knock one over generally depends. Longer barrel? Probably not. But the AC/20 barrel as depicted in MWO is super short, which means higher recoil impulse and more pounds of recoil per millisecond. Without the brace here, this super short and very wide platform could flip itself (particularly if it were mounted on a tank and aimed 90 degrees left or right of the front of the tank).


As you can see here, the slightly longer barrels have almost no recoil. What separates the two videos is a few inches of barrel length, and it (possibly combined with terrain) makes that much of a difference. Imagine if you cut that barrel in the first video in half.


The surface area of the Atlas in width is roughly 3 to 5 Abram's with the tanks lined up barrel to rear. It's only 1 Abram long and that's counting the feet. That cannon barrel is barely 1/2 of an Abram's long. The actual ballistic mount in MWO is approximately 3 Abrams tall if you stacked them back to barrel next to a laying Atlas.

The higher from solid ground a large cannon is, the more 'recoil' has the potential of toppling the frame over. Despite the Atlas's size it should not be able to handle the MWO AC/20 without at least bracing itself. Meanwhile the King Crab (Catapult-body-short, Awesome-wide, and Awesome-width in length too) would easily be able to handle it.

The only specifically mentioned mech to have a single shot 203mm autocannon thus far is the Ebon Jaguar (Cauldron Born). I haven't found a single other mech ever mentioned to have one. Still looking of course.

60 to 90% of lore doesn't get taken into account in Tabletop anyway. Small lasers are sometimes described as multiple arrays of smaller weaker lasers that rapidly fire. MGs usually take a long time to achieve their 2 damage, but in 10 seconds of a turn if you figure the MG is fired for half that time, that's 5 seconds where all the damage is perfectly concentrated. And what about the 10 shot AC/2 against a target moving 90 kph during a 10 second period yet perfectly hitting perfect. Ironically, most mechs are over 60 years old and have been repaired and rebuilt so many times that they supposedly have trouble keeping barrels on target while moving. Even more so the majority of software for battlemechs (most, not all) hasn't been 'updated' or improved upon in 300 years. Tabletop doesn't take any of it into account. After all it'd require a plethora of complicated special rules and "checks" to see what kind of AC/20 you're carrying. It's simply simpler to leave it out.

Things left out of tabletop for simplicity:

• Weapon variant stats.
  
• Damage spread penalties when firing a multi-shot AC (there's 1 or 2 versions of single shot ACs for each range). Can you imagine having to do a dice roll for each of the Pontiac 100's 100 bullets and keep track of the damage spread of 20 damage divided by 100? Or the 10 for the Crusher? What about a 6 shot UAC/20 on ultra mode [double, so 12 shots] when two of them are firing. Can you imagine trying to keep track of "3.333333333333333" damage per shot for 24 shots, complete with all the dice rolls associated with it? It's a bit of a pain.
  
• Recoil penalties of any sort.
  
• Heat generation being divided by number of shots required to reach the allotment of damage.
  
• Ammo count variety based on shots per damage allotment (if 5 shots for an AC/20 that's single shot, it'd be 20 shots for a MG-style Chemjet Gun or 5 bursts of 4 shots for a burst-style Chemjet Gun).
  
• LB variety. Some LBs can fire up to 100 'cluster shot bombs', a specific LB-20 only shoots out 2 very large cluster pellet/bomb things (10 damage each).
  
• UACs are mostly MG-style weapons. Yet no spread against moving targets?
  
• Not every LRM-20 throws out 20 missiles. But we don't see that.
  
• Some lasers are described as firing once instantly. Some as constant beams. Others as 'charging up'. Some as short-term beams (MWO style). None of them are taken into account.

The list could easily go on and on for all the lore things completely left out of tabletop. Just a random thing to mention there's over 44 unique variants of medium laser (this does include the clan medium laser, but does NOT include ER medium lasers or medium pulse lasers) and over 20 sub-variants.

There's approximately 15 Gauss Rifles listed on Sarna. Damage, range, slots, weight, heat and total number of damage units of 15 damage (aka 'shots') cannot change. So how else would they vary? I'm still researching this. But two concepts that came up include a Gauss Rifle that fires a 'alignment shot' for 1 damage (to help you adjust your aim) followed about 0.3 to 0.5 seconds later with the real 14 damage shot. Another was shooting every half cycle for 7.5 damage (at the time of the conception the gauss rifle recycled every 4 seconds. So every 2 seconds beien able to fire a 7.5 damage slug). These two concepts are just unofficial conjecture though.

Here's an incomplete list of some official ACs and MGs. There is a more complete one that I've been looking for which had a lot more of the shot counts listed. I did not write it.

Spoiler

================================
Machineguns
================================
20mm Gatling = 20mm (TRO 3039) skorpion tank entry
M100 = 12.7mm (leithal hearitage) -Phawk
Johnston minigun = 20mm (temptation by war) Ranger VV1 -discribed as caseless (ch 14)
Scattergun = 20mm (temptation by war) DI Schmitt
22mm Gatling = 22mm (TRO 3075) JES 1 entry
================================
Class 2 Autocannons
================================
Whirlwind-L = 32mm (Binding force) BlackJack BJ-1
Whirlwind-L = 30mm (Threads of ambition) Blackjack BJ-1
SarLon = 30mm (TRO 3026) Warrior VTOL
Thor RAC-2 = 40mm (TRO 3058) Warrior VTOL
Mydron Model D-rf (Ultra) = 20mm (Imminent Crisis) Jagermech III
Mydron Model D = 30mm (Threads of ambition) Jagermech
Defiance Shredder LBX = 20mm (Fortress republic) -Catapult
================================
Class 5 Autocannons
================================
GM Nova 5 Ultra = 50mm (Binding force) -cataphract
GM Nova 5 Ultra = 40mm (Illusions of victory) -Cataphract
GM Whirlwind = 120mm (Thunder ridge & Wolves on the border) -Marauder (3 shot)
GM Whirlwind = 50mm (killing field) -Marauder
Armstrong J11 = 80mm or 90mm (Thunder ridge) -Shawdow Hawk
Imperator-A = 80mm (Price of Glory) -Riflemen
Whirlwind = 60mm (Price of glory) -Wolverine
Whirlwind = 90mm (Wolves on the border) -Wolverine
Imperator Ultra AC-5 = 80mm (Storms of fate) -Vulcan & Daikyu
Armstrong AC-5 = 50mm (Double blind) -Clint
Armstrong AC-5 = 105mm (TRO 3075) -Merkava Hvy Tank
Pontiac Light = 40mm (Illusions of victory) -Striker mech
Snake killer LAC5 = 60mm (Battlecorps) -Shadowhawk-9D
Mydron Model RC RAC5 = 50mm (A call to arms & fortress republic) -Legionnaire & Rifleman
Mydron Tornado RAC5 = 50mm (By Temptations and By War) -DI Schmitt
Defiance type J AC-5 = 75mm (Heir to the dragon) -Zeus 6S
================================
Class 10 Autocannons
================================
Luxor-D = 80mm (Price of glory, Ghost of winter) -Centuien
Mydron Excel UAC = 80mm (Patriots and tyrents) -Enforcer
Mydron Excel LBX = 80mm (Patriots and tyrents) -Dragon Fire
Mydron Excel LBX = 80mm (Illusions of victory) -Cataphract
Defiance Disintegrator?= 100mm (end game) -Banshee
Mydron Model B = 80mm (Flash point) -Bushwacker
Federated AC-10 = 80mm (Flash point) -Enforcer
Imperator Code Red = 100mm (Flashpoint) -Challenger MBT
KaliYama = 80mm (Illusions of victory) -Orion
Imperator Code Red = 80mm (Illusions of victory) -Emperor
Imperator-B = 80mm (Warrior en Guard) Urbanmech (implyed to be similer in caliber as the Riflemen)
================================
Class 20 Autocannons
================================
Death Giver = 100mm (Heir to the dragon) -Atlas (15 shot)
Pontiac 100 = 100mm (Heir to the dragon) -Victor ("100 shot cassette loaded cloud" of fire.)
Armstrong = 120mm (binding force) -Von Luckner MBT
Chemjet = 185mm (TRO 3026) -Demolisher I tank (4 shot slow burst)
Crusher SH = 150mm (TRO 3026) -Hetzer Assault gun (10 shot, 2 damage per shot) (or 120mm Threads of ambition)
Defiance Thunder Ultra = 120mm (Patriots and Tyrants) -Blitzkrig
Defiance Disintegrator LBX = 120mm (Patriots and Tyrants) -Barghest -Illusions of victory & The Dying time as well
Kali Yama Big Bore = 120mm (Threads of ambition) -Thunder
Tomodzuru = 180mm (Era Report 3052) -Hunchback (5 shot)
Luxuor Devastator = 120mm (Storms of fate) -Typhoon UAV
Death Giver = 120mm (Storms of Fate) -King Crab (12 shot)

A bit more on this found here. That post and my two posts after (3 total) has plenty on it.

Edited by Koniving, 17 December 2013 - 04:09 PM.

[Strum Wealh]

Also, don't forget to vote for your favorite AC types here!

[BlackYoshi1230]

I did love AC's, but that was, in Mech3 (for me in 2, it was just spam MLs+MGs), when you see those nice yellow balls popping out (I think it was just probably the fact that in 3's main campaign, you had about 1000 rounds in your MFBs to start with, and even then it was considerably hard to use it all up among your lance).

That sound of Ultra/AC 20s... *shudder* Yeah, it's a nightmare to be on the receiving end, but it's a pipe-dream to unload all that awesomeness (that and if your resupply vehicles are stocked, get a second go at it). I gave Paine an Annihilator with dual PPCs and dual AC/10s with 40 rounds of ammo each, it was a min-max killer. Assuming a quad-10X Annie didn't go in his face.

[Araara]

Relevant.

(Credit to SirDubDub for creating it and posting it on mwo reddit)

[jslammer]

ABSOLUTELY LOVE ACs!

o7 to all Federated Suns

[YaKillinMeSmalls]

You know, I wasn't 100% sure I had picked the right faction, and then I saw this thread.

[IraqiWalker]

Skye Storm, on 11 August 2013 - 06:32 PM, said:

That was a great movie, ever notice Jack Black's early role in that film?

Jack Black was in that movie???

[Steel Dragoon]

Those are great videos, but I believe the reason there is no recoil in the second video is they never loaded a round into the barrel...unless I missed it or it was cut out. They essentially fired a blank. I don't think they'd be firing live ammo with a crowd like that anyways.

Other things to consider for recoil.

• Muzzle brakes. They don't seem to be used in BT but you can clearly see them in both videos.
  
• Charge. Artillery pieces can vary the propellant used based on range. Probably moot in the BT universe as AC's are used more like a rifle
  
• Ammo Weight. More mass = more recoil.

Edited by Steel Dragoon, 05 February 2014 - 09:42 AM.

[William Slayer]

Hi, my name is William Slayer and I am addicted to Dakka Dakka.....

Whew, feels good to take the first step and admit you're problem. ;-)

I've loved the Rifleman (Jagermech) since I played TT years ago, and I am excited to be able to play that style again in this game.can you guys give me some other chassis that would work well with my addiction? ;-)

[Viges]

Go to smurfy and find what you want.

[William Slayer]

Viges, on 26 February 2014 - 08:13 AM, said:

Go to smurfy and find what you want.

Will do!

[Fyrwulf]

Steel Dragoon, on 05 February 2014 - 09:40 AM, said:

More mass = more recoil.

Actually, the more mass there is to the weapon the less felt recoil there is, which can be further mitigated by a slower recoil period. I've always viewed every AC as firing one round a second, with the evening out of damage coming down to varying velocities of the different calibers.

As for UACs, especially the 203mm from a Cauldron Born, I view them as having a pulley recoil system similar to the one in the AN/94 assault rifle, which allows it to fire a two shot burst before any recoil is felt, the downside being you get the recoil from both rounds all at once. Not so bad with the small 5.45mm Russian round, but a factor in a huge autocannon. The system is also complex enough that it would explain the chance to jam.

I think I'm going to put together a table with the probable shell weight, velocities, and barrel energy so that everyone can have an idea of what an autocannon actually does. I'll probably use FedSuns manufacturers as a baseline, since everybody knows that the best autocannons come from Davion space.