I don't understand the AC10

[Wolf66]

I’ve recently learned that the AC5 and AC10 have identical damage profiles, and what I thought I knew about the weapons system in this game has been brought into question. To confirm this, I dug up the Sarna weapons chart of every weapon in MW5, translated it into a Google Sheets document, and did some basic number crunching. I’ve learned a great many things from this spreadsheet, specifically the best ways to min/max a chassis into the highest DPM killing machine the game can offer. But that’s not what I want to focus on right now. I want to understand a higher level decision that PGI seems to have made about one of the autocannons. Specifically, what exactly is the point of the AC10?

Also I should clarify, this sheet has every weapon stat, including every version of every gun. Meaning that I have the stats for every version of both the AC5 and AC10.

And I should establish these for clarity:
DAM: Damage
How much damage a single trigger pull can do
DPM: Damage Per Minute
How much damage can be done over the course of one minute
RPM: Rounds Per minute
How many times a weapon can be fired over the course of one minute
HPM: Heat Per Minute
How much heat can be generated over the course of one minute

So, the best place to start is a comparison between the tier one AC5 and AC10.

AC5:
DAM: 5
RPM: 40
DPM: 200
HPM: 20
Weight: 8 tons

AC10:
DAM: 10
RPM: 20
DPM: 200
HPM: 60
Weight: 12 tons

This relationship remains the same at higher tiers, meaning a tier five AC10 has an identical DPM to the tier five AC5

The AC5 weighs four tons less, generates half the heat, its projectiles travel much faster, and it shoots further for an identical DPM to the AC10. They each burn through half a ton of ammo a minute, so you aren’t even getting a more efficient expenditure of ammo with that AC10 and the only advantage it seems to have is higher DAM.

The only argument in favor of the AC10 that I can think of is torso twisting to avoid damage. Take a shot, twist to distribute incoming fire, and twist back to shoot. But even at tier one, we’re talking about a three second reload. That’s about a ninety degree torso twist on your average medium, and you have to re-acquire the target after bringing the guns around. It might make more sense to me if I had more control of the torso. Like the Centurion, free-aim the camera at my target while setting the torso to twist the opposite direction and then only twist back enough to bring the gun on target. Even then, this strategy reduces my ability to use the lasers and LRM pack.

Since I’m sure someone will bring up the burst-fire versions:

AC5 BF
DAM: 6
RPM: 48.39
DPM: 290.32
HPM: 23.23
Weight: 8 tons

AC10 BF
DAM: 12
RPM: 25
DPM: 300
HPM: 60
Weight: 12 tons

The DAM assumes that every projectile fired with a single trigger pull hits

The AC10 BF actually gets a higher DPM than its counterpart, but at the cost of four tons, shorter range, slower projectiles, significantly more heat, and a more difficult to manage five round burst to the simpler three round burst of the AC5 BF. The higher rate of fire also reduces the effectiveness of torso twisting to mitigate incoming fire while keeping damage high.

The rate of fire for every version increases with each higher tier, so even the single shot AC10 loses the torso twist advantage before too long.

With the sheer number of enemies this game throws at you, you really need to be increasing your DPM to take down targets as quickly as possible. And each gun gets better and better at ‘face tanking’ as the tiers get higher and higher with their increased rate of fire. None of which calculates for whatever upgrade slots you may have mounted to any given mech.

The TableTop version of the AC10 makes sense to me, doing twice the damage at a slightly shorter range. The stats seem to have translated over in terms of heat and damage per shot, but the nature of PGI’s weapon balancing has given the AC5 a much higher rate of fire that makes them equal out over the course of a minute. It seems to me like there is no situation where you’d rather have an AC10 over the much lighter AC5.

My ultimate question is this:
Under what circumstance would the AC10 actually be a better choice than an equivalent tier AC5?

[cszolee79]

Pinpoint vs sandpaper.
Plus bigger boom, which is always good.

[Valen]

Strayed is the one to answer this question...

However, you can not compare a turned based table top game (Damage) to real time mechwarrior. Will never work.

Mechwarrior is a real time sim.

Having said this - PGI is know for much Felgercarb when it comes to MW5

[Snek Overlord]

Now i don't understand the ac10 either. Upvote

[Chewy102]

Ballistic weapon in general aren't all that great in MW5 in my opinion. Good alpha damage, but they are vastly more limited in everything else.

Way to heavy in both the weapon itself and ammo required.
Ammo simply doesn't last long enough to be a main damage source.
They simply produce too much heat to be maintain DPS.
And when going for DPS they spread damage to much putting you at risk of taking damage.

Even their alpha damage isn't as good as it should be considering you need to be exact with pin point aim in order to make use of that damage. Add in travel time or bullet drop and it gets easy to miss your shots either in just not hitting anything at all or hitting a different part of a mech to not pop a limb or take out a weapon. And if you can't kill or disable quickly, then you're gonna just soak damage yourself. Maybe even get swarmed.

The biggest use of ballistic weapons are for raid missions where you need to destroy buildings as 1 shot can take out multiple sections of a large building. BF weapons simply murder smaller buildings.

My opinion? Learn to use the AC20 and use that as an alpha hit to pop off weakened mech parts or take out buildings. AC20 is a good all rounder, AC20BF is great in raids but the spread hurts against mechs. Later on you can upgrade to UAC weapons for more DPS, or a Gauss if range/accuracy is more important.

Your main damage source is normally lasers though. Use lasers to weaken a part, then pop it off using a big gun.

[Bovril Brigadier]

Originally posted by Wolf66:

My ultimate question is this:
Under what circumstance would the AC10 actually be a better choice than an equivalent tier AC5?

As already mentioned the only real advantage is having a better alpha.
The AC/5 was buffed with the release of CTA by PGI when it honestly didn't need a buff. A lot of balance decisions in that update were quite questionable.
Things get worse by the way when you bring into question things like the UAC/5 and LBX-10. The LBX-10 Solid Shot is superiour to the AC/10 in virtually every way and for the UAC/5 there's arguably no reason to use it over the AC/5 if you stack ROF upgrades since if you factor in jamming then the AC/5 has vastly more effective DPS over it.

So short answer to everything: PGI suck at balancing.

Bad weapon balancing in Mechwarrior games by the way is nothing new but this is an active case where bad balancing has been caused when there arguably wasn't an issue before.

[6Taylor4]

I like the pretty explosions.

[RealDealBreaker]

They do not have identical damage profiles. You clearly indicate that AC10s deal 10 and AC5s deal 5. That ought to tell you that AC10s have greater 'burst' damage or alpha strike damage. Yes, they have the same dps when you factor in rate of fire, but having more damage on a single shot means you more easily concentrate damage on a single point and when you hit said point, you deal more damage. This means that an AC10 will be more likely to destroy the a CT with a given instance of fire. Also, remember that there is much more at play than basic white room dps calculations (positioning, target selection, accuracy, range, etc.) which further differentiate the weapons.

[BaconHer0]

You have to factor in spread and accuracy between the ACs. In a real time situation, the ability to takedown your opponent 1 cycle faster can be invaluable

[unskilled-]

Well for one boating 4 AC10s on an Annihilator makes more sense then boating 4 AC5s, which leads into the second being hardpoint selection and juggling weight for a mech wherein it makes more sense to slap an AC10 onto your medium hardpoint to balance out the alpha strike potential (ie: you got "free weight" due to not enough other hardpoints ala the Enforcer worth putting extra weighty weapons into). I guess the third being its all you have, whether new game or early game before finding the good stuff.

But tbh AC5/10s are pretty meh since very few mechs have more than one medium ballistics slot to try and slap deuces on, and even then the LBX-10-SLD solid shot is superior in every which way making the AC10 entirely useless when you find one.

And then you have the UAC/5 which is superior to all three of them and then some its such a godly weapon, the Tier 5 version being outright OP and can turn average mechs into Word of Blake levels of destruction and slapping it onto a Hero mech like Quarantine could probably solo the entire clan invasion of Tukayyid.

Maybe if they brought weapon sizes (2 and 3 slot auto cannons) back and not weapon slot sizes (small/medium/large) the AC5/10s could find quixotically find their niche roll despite being an overabundant weapon via being (like in MWO) a smaller more compact version of the UAC/5 (10s too) and LBX autocannons while also being twice as durable with ammo that doesn't go off if you look at it funny.

[owen8964]

You do not "understand" the AC10. You become one with the AC10.

Om Mani Padme Boom.

[pyr0kid]

autocannons are a complete joke.

lasers will do the same thing in less slots, not explode, not run out of ammo, with less tonnage, and arguably works better at legging mechs if your aim sucks.

ac20 is the only one with enough kick per ton to respect.

[BaconHer0]

Originally posted by pyr0kid:

autocannons are a complete joke.

lasers will do the same thing in less slots, not explode, not run out of ammo, with less tonnage, and arguably works better at legging mechs if your aim sucks.

ac20 is the only one with enough kick per ton to respect.

Nah, Lasers require you to hold on target for full damage. Often it's spread out to across a mech's structure resulting in lowered kill potential. Pulse mostly gets over this but it generates so much heat

With ballistic weapons, you don't have to hold on target, allowing you to do flick shots that will dump full damage on a single structure. This value cannot be understated

Also, ballistic weapons can be shot further than the displayed HUD range with reasonable drop-off, so you can still plink targets at quite an impressive distance

[climbingeastofwinter]

In situations where you can control line of effect (with cover), a mech with ac/10 trading shots with a mech with an ac/5 could trade 10 damage for 5 damage, duck into cover for the cooldown, then reemerge and fire to trade again 10 for 5. This can also be the case if you're in a brawl, circling, and can put a target in a position where it can't torso twist to face you without exposing it's rear to an ally who would have a perfect back shot. In such a case, having a slower firing ac may be much better because one or both parties may not be able to take full advantage of the quick cooldown of smaller ac's because of torso facing needs.

If you're trading a shots nonstop though, and perhaps at longer range, an ac/5 may make more sense than an ac/10 because your hit rates are going to depend to a degree on projectile velocity and accuracy can be an issue, again depending on the situation. The smaller ac's have longer effective ranges for full damage. These two things, projectile velocity and damage falloff, can work together to make the smaller ac's perform much better than larger acs.

[PhoenixFury]

The theory with ACs and, ultimately, a lot of "big guns" in battletech tabletop was that the larger the gun's damage, the less efficient it needed to be, either in heat, range, tonnage or all of the above, to make up for the fact that it deals a lot of damage in one spot. Autocannons have, historically, most emphasized either this, or heat efficiency over range depending on their size.

Each gun is rolled for location individually, meaning firing four medium lasers at a target may do as much damage as a single AC/20 at the same ranges, but over four locations. An AC/20 weighs 14 tons, need at least one ton of ammo, and generates 7 heat, while the MLAS weigh four, generate 12 heat and use few enough criticals we can simply call the cluster 9 tons to account for extra sinks. Ultimately, the lasers win hard on a mathematics standpoint.

In practice, an AC/20 kills things because 20 points to a location on a medium or light mech will probably break stuff either by complete destruction or critical roll, and a headshot will kill any mech, regardless of weight. 20 points also forces a piloting check against knockdown. AC/20 stronk.

"So why does this matter in mechwarrior 5, Phoenix?"

Because ultimately the porting of mechwarrior online and by extension, 5, from tabletop has been a bit fraught with difficulty. It's come a long way since the beginning, but this is one of those problems that creeps up on you. Fundamentally, autocannons don't work in conjunction with group fire. If you allow the player to pull a trigger and land multiple weapons on the same spot, you've essentially broken the (tabletop) game balance. This is why lasers have burn times, this is why LRMs and SRMs spread, and so forth. It's also why the 4P is a better hunchback variant than the 4G in the videogames.

Doubling armor values didn't help either, because now a single AC/20 round won't reliably destroy a component or put that component internal on mechs below assault weight. It often won't reliably headshot either, but perhaps come close. This was required for game balance and, by and large, was regarded as a good move.

But that's the long story why autocannons, particularly big-bores like the AC/10 and 20 don't feel good. They simply don't benefit from what was desirable about them in the tabletop game. AC/10s were already a compromise between the 5 and 20, and especially suffer as a result.

[Wolf66]

Normally I let these conversations play out however they naturally want to go, but this post got picked up again for some reason. I should probably explain, I had accepted Strayed's answer of: PGI is weird about their weapon balancing and only they know why they did it outside of the studio.

I'd be fine if all the other ACs got a damage buff to be a bit more in line with the current AC5, but I'm not going to hold my breath.