Is it actually bad to put ammo in the center torso?

[Trailblazer]

I'm talking 3025 here. Obviously things change when CASE is a possibility.

But think about it this way: what is the marginal harm of hitting a CT ammo crit. Yes the mech is destroyed. But if it didn't hit the ammo, you'd have had an engine or gyro crit instead. Gyro is extremely crippling, that mech is almost out of the game. Engine is less bad but in 3025 that five heat is a real problem.

Yes there are through armor criticals. If you play with floating crits the CT is no worse than anywhere else. And even if you don't the odds of rolling a TAC and then rolling an ammo hit are less than 1 in 200.

I wonder whether the widespread aversion to CT ammo bins rests on a statistical fallacy. Open to opposing arguments though.

[ThePW]

There is a reason why the Crusader 3R is as common as dirt (as far as parts go): Either they make so many per year or the numerous parts available ONLY because that's all that's left of Crusaders when someone does several 1 in 36 odd rolls of their dice to crit that SRM ammo...

[Hellraiser]

More Armor
Guaranteed 10 other "crit soak" slots  (Not that those are any nicer really)

Ideally you would put ammo in the Arms w/ Arm Mounted Weapons & some Heatsinks too.

Imagine the mentioned Crusader that moved the LRM ammo from Torso to Arm where it would have 8 crits to soak it up.
  No more 1 crit BOOM for side torsos,  which is far more likely than taking out the SRM/MG ammo in the CT honestly.

Something like swapping MG for Flamer & reducing SRM racks like the D/L does would net you less ammo in the CT & a couple HS to pad the opening with.

That kind of placement change makes for something that is quite a bit more durable in terms of criting the ammo.

You want really safe?   Stick it in the head :)

[Prospernia]

I've put worse in the Center-torso as a critical.  When running Mechwarrior, RPG, what am I suppose to do with a tech that insists on riding along with the mechs?

[Psycho]

If you play with floating crits the CT is no worse than anywhere else.

From long, sporadic playing, to me that point as an assumption based on modern play. In my early days, floating crits either wasn't a thing or wasn't a thing we used, which made those CT ammo bins loom far larger. Couple it with the ammo often being MG, or maybe SRM - ammo that you absolutely weren't going to get through during a battle - and it felt more like carrying a bomb.

I'll also counter-argument with a question of which is more crippling: an engine crit, a gyro crit, or your 'Mech in small pieces scattered all over the hex? 

Ammo explosions are never good, but if you had ammo that you were running through in a side torso, at least there was a chance it wouldn't blow all the way through. 400 points worth of MG ammo nestled right under your engine? Nothing's coming back from that.

[abou]

The highest amount of armor, density of crits, and use of the floating crit rule often means that ammo in the center torso is the safest place in 3025 play. It is not unreasonable at all.

ThePW does bring up a good point with mechs such as the Crusader; however, there are still caveats. Ammo explosions transfer directly through internals. Crits also transfer to the next location if the struck location is empty. So even an ammo hit in the arm with a half ton of LRM ammo will probably kill the mech.

The Crusader is for brave pilots. That or you empty your bins from long range as soon as you can.

[garhkal]

From long, sporadic playing, to me that point as an assumption based on modern play. In my early days, floating crits either wasn't a thing or wasn't a thing we used, which made those CT ammo bins loom far larger. Couple it with the ammo often being MG, or maybe SRM - ammo that you absolutely weren't going to get through during a battle - and it felt more like carrying a bomb.

I'll also counter-argument with a question of which is more crippling: an engine crit, a gyro crit, or your 'Mech in small pieces scattered all over the hex? 

Ammo explosions are never good, but if you had ammo that you were running through in a side torso, at least there was a chance it wouldn't blow all the way through. 400 points worth of MG ammo nestled right under your engine? Nothing's coming back from that.

Having a full ton of MG ammo ANYWHERE without case, is gonna make any mech go boom..

[DevianID]

Floating crits is a big, looming presence in this discussion.

Floating crits makes the CT take less raw damage, by moving 13% of the damage the CT would take off the CT.  So just from raw damage alone, floating crits makes you take less CT crits by reducing the hits to structure.  In a mech like a crusader or thunder bolt with CT ammo, turning 40 CT damage to 35 is 1 less roll for crits on structure.

As for the TAC itself, well with core rules you will see 1+ CT TAC per 86 hit location rolls.  About 1 time per average 4v4 game.  With floating crits, well now you will play 9 average game and see 1 TAC to the CT.  So it makes a massive difference.

With floating crits, a mech like the hunchback/marauder is better off putting the ammo in the CT then the exposed left side.  Without floating crits, you can protect your left side, so there is no chance of an Ammo TAC when played well, so you dont want ammo in the side torso unless you know all the incoming damage will be from the rear.

I don't like how floating crits makes the game take longer and how it changes a players interactions for protecting/targeting side torsos.  The famous CT ammo bomb on mechs becoming the smarter storage location for ammo is not how the lore was written, but with floating crits my personal games show the crusader never losing the CT ammo bins but the side torso bins are way more dangerous with floating turned on--ive lost multiple crusaders to side torso floaters IRL.

[Frabby]

It is always a bad idea to have ammo in the center torso. Yes, the chance to hit one of the two freely useable crit slost there is only 1 in 6 (2 in 12) if you score a critical hit. But all the other slots are also pretty bad: Gyro hits are crippling and engine hits are at least bad, sometimes also crippling.
So you would definitely be better of to install a pair of heat sinks as padding and protect your engine and gyro, by having a 1 in 6 chance for a CT crit to be not a crippling one.

It is arguably a worse idea to mount ammo in a side torso because it can end up a 1 in 1 chance of leading to an ammo crit there, and side torsos take a through-armor crit instead of CT on snake eyes if the attack comes from a side location.

That's why in my opinion ammo is safest in the head (which may get blown off but hardly ever suffers a crit), followed by arms.

When using floating crits, nothing much changes the equations for me really. When you're rolling for through-armor crit instead of going straight for torso, torso locations remain the statistically most likely regions to be hit. CT remains the one location where a single crit will often cripple a 'Mech and side torsos are either designed as ammo bombs or they aren't irrespective of wether or not you're using floating crits.

[DevianID]

Floating crits has a massive impact on the equations.  While you may not notice these events very much, they do have a very large impact.  Like you say, a crit to the CT is very bad.  But floating crits reduces CT TA crits 88.5%, and damage 13%.  On something like a crusader, you take a side ammo hit 10/36 times you take 1 confirmed floating TAC, and a CT ammo crit 1.166/36 times.  So you will explode 8-9 crusaders from TAC ammo hits to side torsos before a single one goes up to a CT ammo hit, just because of floating.  Thats a massive difference.

As to ammo in the head, yeah, thats better if you allow customs.  But so is all energy, and all energy with lots of ablative HS REALLY loves floating crits.  It's equal to rerolling head hits on an energy boat.

[SteelRaven]

Really depends on your personal philosophy/play style and your game. If you play every game as a grinder or if you play campaign where repair and savage is a big part will make the difference.

[avon1985]

Speaking from the other side. Back many years ago a group of us were playing a game and I hit a Crusader with an AC2 round at long range.  It was the only damage done to the Crusader durning the game thus far.  Rolled location center torso possible critical, rolled on critical hit chart, one critical.  Then rolled for where, yup you guessed it ammo, 100 rounds go MG ammo goes BOOM.  Every game after that my friend when playing with that Crusader dumped his ammo on the first turn. 

[Gorgon]

That's the thing, though - TAC'ing the ammo is a rare case, but when it happens, the memory sticks.

Another thing is the center torso is sturdy. And more points internal structure means you get more chances to role for crits. Arms have a better chance of being shot off with only one or two chances at a crit.

[Atlas3060]

Really depends on your personal philosophy/play style and your game. If you play every game as a grinder or if you play campaign where repair and savage is a big part will make the difference.

Ah good someone else brought up what I wanted to say.
For one shot games, the idea of ammo in the center torso isn't bad per se for 3025 era stuff because there's no CASE to save you.
However if you're playing a long term game, one with salvage, then yes it is horrible to keep ammo stored there because of the Destroyed versus Truly Destroyed rules.

[Psycho]

Having a full ton of MG ammo ANYWHERE without case, is gonna make any mech go boom..

True, though my point was more that when ammo is being carried, you're more likely to see MG ammo in the CT (Warhammer, P-Hawk, Stinger, etc) than something like LRM or AC ammo that ends up more often carried in the side torso, and in volumes that you could use up during a game (Catapult, Trebuchet, Marauder, Archer, etc). A 10-20 point explosion *could* be survivable in a side torso.

[Trailblazer]

DevianID, you bring up some good points but in the end I disagree.

Floating crits makes the CT take less raw damage, by moving 13% of the damage the CT would take off the CT.  So just from raw damage alone, floating crits makes you take less CT crits by reducing the hits to structure.  In a mech like a crusader or thunder bolt with CT ammo, turning 40 CT damage to 35 is 1 less roll for crits on structure.

This is a good point, but again--any CT crit is a very big deal.  There's a 40% chance that one extra crit would have hit the gyro and put the 'Mech on the ground and a 60% chance it would've wrecked your heat curve.

As for the TAC itself, well with core rules you will see 1+ CT TAC per 86 hit location rolls.  About 1 time per average 4v4 game.  With floating crits, well now you will play 9 average game and see 1 TAC to the CT.  So it makes a massive difference.

Yes it does, but even without that massive difference think about the odds of actually hitting the ammo.  1 TAC per 86 hits means one ammo explosion per 516 hits even on a Crusader.  It's a little more than that because of double and triple crits but it can't be worse than 1 in 400.  If you lose a 'Mech once every five games that is not so bad, especially because there's a good chance that TAC will happen late in the game anyway after the 'Mech's already done some good.  Also a good chance you'll roll that 2 after the CT armor is already pierced anyway.

And with the Crusader we're talking about two tons.  If you just put one ton in the CT it's about half that chance of an ammo TAC.  You could play every week for a year and not see that happen.

Compare this with what has to be almost a 50% chance of a Marauder 3R eventually exploding in any given game unless you dump the ammo!  It's not that CT ammo is safe, but it is safer than side torso ammo unless the side torso is really crit-packed.

With floating crits, a mech like the hunchback/marauder is better off putting the ammo in the CT then the exposed left side.  Without floating crits, you can protect your left side, so there is no chance of an Ammo TAC when played well, so you dont want ammo in the side torso unless you know all the incoming damage will be from the rear.

I don't agree.  Protecting your left side by turning your right toward the enemy requires very specific maneuvering.  It will reduce the firepower your can point toward your targets on average, since you can't always twist your whole front arc into alignment with your target, and it will waste valuable MP that could be spent on running up your TMMs.  And you can't always accomplish it if your opponent has mobile flankers. 

It's worth doing with a Marauder, yes, but only because the Marauder's ammo is so outrageously vulnerable in the LT--much more than it would be in the CT even without floating crits.

[Trailblazer]

Speaking from the other side. Back many years ago a group of us were playing a game and I hit a Crusader with an AC2 round at long range.  It was the only damage done to the Crusader durning the game thus far.  Rolled location center torso possible critical, rolled on critical hit chart, one critical.  Then rolled for where, yup you guessed it ammo, 100 rounds go MG ammo goes BOOM.  Every game after that my friend when playing with that Crusader dumped his ammo on the first turn.

This is the equivalent of a poker player folding too many hands because they've had some "bad beats."  It's a statistical fallacy that will lose on average in the long run.

[Vonshroom]

Yes, its terrible to put ammo in the CT. I will play with mechs that have it, and its not a "game ender" by any means but I won't play with a force that exclusively has CT ammo bins, and certainly don't prefer it.

The ability to get TAC'd from the front (the direction your mech should be facing). or rear on snake eyes is really bad. Sure any hit to the CT that goes critical is bad, but even an engine or gyro hit is better than anything ammo related in the CT.

With many ammo centric mechs in 3025 era play its common to hoard a few last shots or maybe a volley of LRMs and either dump the rest or simply expend it. This makes sense as a good solid volley can turn the tide of a battle, but when the armor margin starts getting thin you dump it, or if there's only a shot or two your mech can probably withstand the explosion if there is a crit. CT ammo bins don't allow for this flexibility so it is either all there or all dumped. This can be a big drawback too.

I don't get people who like it there because its the most "crit padded". Sure, but its not like its Single Heat sinks padding the crit, its your gyro, engine, etc. and if it does hit the ammo...

[General308]

The highest amount of armor, density of crits, and use of the floating crit rule often means that ammo in the center torso is the safest place in 3025 play. It is not unreasonable at all.

ThePW does bring up a good point with mechs such as the Crusader; however, there are still caveats. Ammo explosions transfer directly through internals. Crits also transfer to the next location if the struck location is empty. So even an ammo hit in the arm with a half ton of LRM ammo will probably kill the mech.

The Crusader is for brave pilots. That or you empty your bins from long range as soon as you can.

Yes but with standard rules the CT is the only location that can take that crit on a CT  And the number to hit the CT is the most comon from the front.


My answer is is better than putting it in a Side torso if you have no crits to soak it up for sure.   So sometimes it is the best place to put it sometimes not.  In 3025 odds are it doesn't matter unless you have used up almost all the ammo in the ammo slot that gets hit.

[Paul]

But floating crits reduces CT TA crits 88.5%, and damage 13%.

I'm not sure I follow your math here.
The odds of a through-armor crit don't change. The location will now be a CT 8/36 of the time after all. That's 22%, so a reduction of 78%.
Not sure how you see it reducing damage itself by a whopping 13%, since the through-armor crit chance is just 3%, and filtering it for now locations only reduces that to 0.67%. So the chance for total damage to the CT goes from 22% to 19.67% per shot.


Concerning the OP: any ammo hit is more likely than not to be a death sentence in 3025. Putting it in the arms instead of the CT doesn't drastically change the math. Meanwhile, at least it's always crit-packed and protected by lots of armor in the CT. Especially when you're good at retreating units before crit hits become common, having it in the CT does reduce how likely you are to see any ammo explosion.

[Prospernia]

One way to get to prevent an ammunition-explosion in the center-torso is to, use, up your ammo as fast as possible. It's a great place to store AC/20 ammo, because in most cases, you're going to have used it up before the chances of a critical-hit occur.  Just always plan on firing your weapon using ammo from the CT, even if the chances of hitting are low.

[House Davie Merc]

If I were in a MAD-3R I'd rather have that AC/5 ammo moved to  the CT and push a heat sink where the ammo was any day.

[Retry]

I don't get people who like it there because its the most "crit padded". Sure, but its not like its Single Heat sinks padding the crit, its your gyro, engine, etc. and if it does hit the ammo...

It's opportunity cost.

Say you have one free ton of ammo and two free SHS, and you want to put 'em in the torso.  You could put 1 HS per torso and a ton of ammo in the center, or put the ammo in a side torso and HS in the other two sides.

Without allocating anything, all torso crits, left right and center, go straight to the center and hit Engines 60% of the time and Gyros 40% of the time.

1st Engine hit, passive +5 heat generation.  On a lot of 3025-era 'Mechs with 10ish heat sinks, this more than halves your firepower unless you either have one of the few 'Mechs that started off with a lot of heat sinks to begin with (Awesome), or your 'Mech didn't have anything in the way of meaningful firepower to begin with (Wasp).  Otherwise you're mission-compromised.  2nd Engine hit, passive +10 heat generation.  Unless you're something like Awesome, this is effectively a mission kill.  3rd hit is always a kill.

1st Gyro hit, +3 PSR penalty, auto-PSR on hit.  Often (though not always) accompanied by other PSR-causing effects that turn such as taking 20+ damage, which causes another roll with the heavy penalty.  Unless your pilot is excellent, chances are good that this hiccup turns into a mission kill, since a 'Mech that just fell (and has troubles getting back up) is going to be a VERY easy mark next turn.  2nd Gyro hit, +6 PSR penalty, auto-fall.  Definite mission-kill.

Ammo explosion, your pilot takes damage and your 'Mech explodes.  Basically doesn't matter where it's located, CT or arm, your 'Mech is dead, unless you have CASE or are lucky enough that you only have 1-2 shots in the bin on a very heavy 'Mech (which I think I've seen... twice.)

Heat sink crits, of course, are much more generous.  You just lose a small amount of cooling.  Not the end of the world, and makes a good crit sink.

So your choice of crit placements looks roughly like the following:

Ammo in side torso:
-1 Side torso is relatively safe on Crit (HS sink)
-1 Side torso results in mission-kill on Crit (ammo)
-CT results in combat-ineffective for most 'Mechs on 1st crit, near guaranteed mission-kill by 2nd-crit, with a small ~9% chance of the crit being sunk in a relatively harmless matter (HS sink)

Or Ammo in CT:
-2 Side torsos are relatively safe on Crit (HS sinks)
-CT results in combat-ineffective for most 'Mechs on 1st crit, near guaranteed mission-kill by 2nd-crit, with a small ~9% chance of the crit being a guaranteed mission-kill (ammo)

Of course, with a small number of 3025 designs, as well as DHS designs, the engine crits are not as crippling.  But if you have that then you probably have CASE as well, so you can use that instead of CT stuffing ammo.

Otherwise there's a clear reason one may prefer CT ammo over side torso ammo: CT crits are already crippling, to the point that 1 will usually mission-compromise or mission-kill having 2 will almost always mission kill a 3025 era 'Mech, even before knowing where the crits actually hit.  The cost of putting in yet another thing in the CT that can mission-kill the 'Mech is small, since that's not far off from the baseline assumption.

Putting ammo in a naked side torso however has a major opportunity cost: There is now two locations whose crit will be a likely mission kill.  Even without floating crits, those side torsos can still suffer TACs, and IME (and probably statistically too, but it's been a while since I checked) those side torsos tend to get stripped of armor more quickly than the CTs to take internal crits too.

For a more concrete example, sure, a Crusader CDR-3R's 2 tons center torso ammo isn't improving its survivability, but they're having far less impact on the overall survivability of the platform than its 2 side torsos which both have unpadded ammunition bombs.  When I see those on the field it's almost always those side torso culprits that are causing those to light up like the 4th of July.

[DevianID]

I'm not sure I follow your math here.
The odds of a through-armor crit don't change. The location will now be a CT 8/36 of the time after all. That's 22%, so a reduction of 78%.
Not sure how you see it reducing damage itself by a whopping 13%, since the through-armor crit chance is just 3%, and filtering it for now locations only reduces that to 0.67%. So the chance for total damage to the CT goes from 22% to 19.67% per shot.

Looks like your base numbers are wrong, that's why your % disagree with me.

The CT isnt 8/36.  That's probably the number that ruined the rest of your calcs.

As for damage to CT, take the number of dice combos that hit the ct, and divide by the number of dice combos that hit the CT with floating on.  Its 13% more damage to the CT without Floating.  So it's not only do you take 83% less TACs to the CT with floating cause they go elsewhere, but the 13% damage is worth 1 less crit roll on structure on a heavy mech.

A few people hit the nail on the head.  All ammo is bad for survivability, so crit packing in an arm so there is 11 non-ammo slots with 1 ammo is the most survivable... But that isn't the situation here.  The OP didnt seem to be talking about fully crit padded ammo, so the option is ammo in an otherwise normal spot or the CT for the free crit padding there.  There are Monty Carlo simulations for specific combos if you want a very specific example crunched like a banshee, but usually because of rear risks and side targeting, ammo in a naked side torso is worse then in the CT.

Battlelytics on YouTube runs destructive simulations on mechs, using standard (non floating) crits, so for further reading you can check out the ammo versus head versus CT destroyed numbers for the mechs they have analyzed so far.

Edit: so for example.  A rifleman dies to CT ammo explosion ~5% of the 10000 simulations.  A hunchback 4h, which has 2 tons in the left torso padded with 5 heat sinks, dies to ammo explosions 14% of the 10000 simulations.  With floating crits, the rifleman would take less and the hunchback even more.  So yeah, barring a really specific situation you explode less with ammo in the CT, unless it is unreasonably protected for 3025 like in the head or fully packed arm.

[Paul]

The CT isnt 8/36.  That's probably the number that ruined the rest of your calcs.

Let's find out:
CT is hit on location 7 of the chart, which occurs 6/36 times.
Also on location 2: 1/36 times, 7/36 total.
Not 8; not sure why I thought that.

With Floating, after getting the 2 result, you have a 7/36 chance of it confirming CT. That's 19.44% of the time.
So after floating crits, the chance of hitting the CT is:
7: 16.67%
2 w/ floating: 2.77% * 19.44% = 0.54%
Total chance to see the hit be on the CT is then 17.21%
VS 19.44%

So it's 88.5% as likely to occur, not a 88.5% *reduction*. The reduction is 12.5% (which I guess is close enough to 13)

[phoenixalpha]

Every post seems to ignore the rear armour situation. You can be all armoured up at the front, but rear attacks are way deadlier for going boom especially in mechs like the 3025 Crusader/Marauder which have big ammo bombs and nothing to protect them apart from a few paltry points of armour. Mechs like the Blackjack/Enforcer suffer badly from this. In fact if memory serves *way* back in the day I played a game where an Enforcer failed its piloting roll, fell backwards, the fall damage went through the armour into the ammo bin... nothing worse than self induced kerboom.

[OatsAndHall]

Yes, I think it's a bad idea, for a few reasons:

1. You have the highest probability of taking hits to the CT, according to the 2D6 curve. Even if you're playing with floating crits, the CT is still the most likely spot to get popped.

2. Yes, getting hit in a gyro is crippling but it's survivable. Losing the whole CT isn't. An ammo explosion is nasty is a 3025 game but there's a chance the mech will walk away if the ammo is in an arm or the LT/RT.

But, I s'pose this all depends on what style of play someone is looking for in a 3025 game. Ammo explosion rules for the era are intentionally catastrophic given that mechs don't dish out a lot of damage each turn but they sure can absorb it. Having an ammo crit go up adds some excitement to the game, keeps people from only fielding ballistic/missile boats (single heat sinks) and can speed up the game a bit.
 

[Hellraiser]

Let's find out:
CT is hit on location 7 of the chart, which occurs 6/36 times.
Also on location 2: 1/36 times, 7/36 total.
Not 8; not sure why I thought that.

With Floating, after getting the 2 result, you have a 7/36 chance of it confirming CT. That's 19.44% of the time.
So after floating crits, the chance of hitting the CT is:
7: 16.67%
2 w/ floating: 2.77% * 19.44% = 0.54%
Total chance to see the hit be on the CT is then 17.21%
VS 19.44%

So it's 88.5% as likely to occur, not a 88.5% *reduction*. The reduction is 12.5% (which I guess is close enough to 13)

I'm sure the error was just a brain far of thinking "To Hit Location #"7" + 1 v/s  6/36 + 1, easy enough mistake to make.
But, what I'm not seeing is math in there for damage coming in from the side arcs which account for 33% of incoming fire.

That will change things quite a bit I think, though, floating crits then brings that a bit closer back to those #s.


Either way, the entire TAC issue is still insanely small & I'll take a crit padded CT for a single ammo slot v/s a Side-Torso solo slot any day.
Salvage rules or not, unless the ammo is basically gone any 1/2 ton or more explosion is going to rip most any mech apart.

[Paul]

I'm sure the error was just a brain far of thinking "To Hit Location #"7" + 1 v/s  6/36 + 1, easy enough mistake to make.

Plausible!

But, what I'm not seeing is math in there for damage coming in from the side arcs which account for 33% of incoming fire.

It doesn't though: you can have entire games where the side locations are never used. Or where they get used more often than front/rear. It's too situational, so if you're evaluating the relative effect, you go with a baseline and compare.

Either way, the entire TAC issue is still insanely small & I'll take a crit padded CT for a single ammo slot v/s a Side-Torso solo slot any day.
Salvage rules or not, unless the ammo is basically gone any 1/2 ton or more explosion is going to rip most any mech apart.

Yeah, totally agree.

[Hellraiser]

It doesn't though: you can have entire games where the side locations are never used. Or where they get used more often than front/rear. It's too situational, so if you're evaluating the relative effect, you go with a baseline and compare.

Agreed that it's situational & that it could be more/less.
But disagreed that you just go w/ Front & ignore the rest.
I'd rather just assume that each hex side/Arc gets an equal 1/6 of fire & let the law of averages work itself out over time.