'Mech Mortors? How's that Get Fun?

[Goose]

Are they AMS-Proof© or some-such?  ???

[Syzyx]

Mech Mortars are AMS-proof, since they're not missiles, and they also work well killing annoying speedy things since airburst ammo targets the hex, not the unit.

[Empyrus]

Are they AMS-Proof© or some-such?  ???

Yes.
AMS-proof, LRM range, damage and hits like SRMs, and have some hilarious ammo options.
Are they great? Probably not. But they're far from the worst thing.

[Goose]

… have some hilarious ammo options.

Now you're talking my language: What's the story?

[PuppyLikesLaserPointers]

But, I recommend to not use that, unless you face APDS. Shooting LRM against AMS actually makes the better damage output than the mortars with same class, because mortars are too weak. There is a reason why it is hard to see - that's just because it is simply outdated.

[Daryk]

Except for the AOE option.  When fast movers are on the table, AOE weapons are priceless.

[PuppyLikesLaserPointers]

Yep. Airburst has very low damage but it doesn't cares for the enemy's movement because it is AOE attack.

[Empyrus]

Now you're talking my language: What's the story?

Well, there's airburst, targeting a hex bypasses most defensive mods. Not too much damage, but it does hit everything in the hex. Also clears infantry pretty well.
Anti-personnel mortars are useful for clearing infantry from long distance, not too many options for that.
Flare mortars aren't the most useful things unless playing with night rules. (Under TW/TO rules, Flare LRMs don't actually exists as usable munitions.)
There's smoke option, never a bad thing.
Spheroid mortars also have semi-guided option.

Okay, not that special but you got options. Never know when they might come handy.

But, I recommend to not use that, unless you face APDS. Shooting LRM against AMS actually makes the better damage output than the mortars with same class, because mortars are too weak. There is a reason why it is hard to see - that's just because it is simply outdated.

Mortars aren't a LRM replacement, or even an alternative really. Rather, they're long range crit-seekers. They're not that stellar against 'Mechs unless those have weakened armor or even holes in it already, just like SRMs. Against vehicles mortars are far more deadly due to their many individual hits.
Now, one might suggests using LB-Xs and the like, but those don't offer indirect fire option. Enemy armor column rolling somewhere? Get a spotter in position and fire a bunch of mortars and watch the enemy vehicles getting immobilized or whatever else nasty things crits tend to do to vehicles.

It is unfortunate mortars are pretty rare. Off-hand, i can think of only Gurzil (or some such), an experimental version of the Ha Otoko, and the Ant Lion. The last is excellent if very specialized mortar carrier, but pretty exclusive and arguably too specialized for general use.
Wish there were mortar configs for some Omnis. Not always useful, but having them as an option would be nice.

[Retry]

As others have said, Mech Mortars are AMS proof.

That doesn't amount to much, though.  In terms of raw damage, a regular AMS chops the LRM-20's average damage from 12.7 points down to 8.1 points.  The MM-8 does 10.17 on average, which is a small advantage considering Mech Mortars are such a pain to use.  Putting ART IV on that LRM-20 or using a Narc beacon is enough to equalize the two.  The extra ammo + heat sinks that the MMs need could easily be put into either option.  That, and barrages of LRM-5s are perfectly sufficient to outright overwhelm AMS.  The theoretical advantage of ignoring AMS is entirely negated by both the unwieldiness of MMs and that AMS is somewhat toothless to begin with.

So after that, all we've got left is the alternative ammunition.  There's smoke, anti-personnel and semi-guided, but LRMs do that just as well if not better and have larger ammo bays.  So you're left with airburst & flare ammo.  Flare has no LRM counterpart, suprisingly enough, but it's only useful in night-time scenarios that are rarely ever actually played (partially because they're not much fun to play as-written).  Airbursts fire at a hex (though unlike normal weapons, they don't get the "immobile" to-hit bonus for doing so), deal 1 AOE damage per shell (1D6 vs conventional infantry).  That's potentially a reason to take mortars.

But even then, you can re-purpose the LRM to act as a makeshift Airburst: Mine-Clearance Ammo.  Mine-clearance also targets the hex, but it does benefit from the immobile target bonus (far more accurate).  A LRM-5 does 1 point of AOE (as much as an Airburst MM-1), the LRM-20 does 5 (bested only by the MM-8 at 8 ).  Against 'Mechs and BA, LRM mine-clearance is competitive at gnawing off BA and fast targets, though it loses out at killing conventional infantry. (not that infantry are going to be all peachy after getting hit with AOE.

Oh, and get this: Mine-Clearance ammo is good at clearing mines.  Quite a nice bonus!

So if you're thinking about getting a Mech Mortar just for air-bursts, it might be simpler and easier to just turn a few LRMs you're already lugging around into poor-man's Airbursts by adding Mine-Clearance into the mix.  By the time you might want the "real-deal," you might just jump to the real AOE sources like Artillery Cannons or just the full-scale Artillery Pieces.  Honestly, Mech Mortars are just not appealing.

[Empyrus]

Pretty sure rules got updated long ago to make mine clearance missiles ineffective (EDIT meaning, don't bother vs BAR6+) at anything except their intended role.

[Retry]

Pretty sure rules got updated long ago to make mine clearance missiles ineffective (EDIT meaning, don't bother vs BAR6+) at anything except their intended role.

That'd figure.

The better question is what rules do I use that they haven't errata'd out?

[Syzyx]

That'd figure.

The better question is what rules do I use that they haven't errata'd out?

Uh... Are you still playing the game with 2d6? I think that's still valid. ;)

[Red Pins]

I'd like to use these, but nobody ever gave me a straight answer for or examples in game terms w/ t/h calculations.  Plus errata, apparently.  Too bad.

[PuppyLikesLaserPointers]

Average damage of some weapons are...

Code: [Select]

LRM-5: 3.166..
LRM-10: 6.3055..
LRM-15: 9.5
LRM-20: 12.6944..

When against AMS:
LRM-5: 1.8611..
LRM-10: 3.9722..
LRM-15: 6.25..
LRM-20: 8.0833..

When against LAMS:
LRM-5: 1.44..
LRM-10: 2.722..
LRM-15: 4.166..
LRM-20: 5.5833..

'Mech Mortar 1: 2
'Mech Mortar 2: 2.833..
'Mech Mortar 4: 5.277..
'Mech Mortar 8: 10.166..


Well, only by the damage per turn, mortar can be a viable weapon. But the problems are...
-AMS is not so popular option in the first place
-heavier round than LRM(for 'Mech Mortar 4 and 8 )


If you want to use that, then I recommend 'Mech Mortar 1 or 8. For 1, As you know small sized tube is more efficient, and there is no Artemis for mortar either. 8 is five times stronger and heavier than 1, so it is not that bad one. Picking the best one can be cheesy, but who cares, for picking outdated weapon group already proves that you are far from the optimization.

Also as you can see, only 'Mech Mortar 1 and 8 can beat LRM with same class when it is suffered by AMS. 'Mech Mortar 2 and 4 are weaker than LRM-10/15 against AMS. Only against LAMS(or using option rule on TO that rolling less than 2 causes AMS to kill all the missiles) it may have some hope.

Also 4 and 8 requires you the more rounds so you need to pay more tonnage for the ammo(an 1 ton of LRM-15/20 ammunition gives you 8/6 shots but an 1 ton of 'Mech Mortar 4/8 ammunition gives you only 6/4 shots). So tonnage wise the overall performance of 'Mech Mortar 8 is slightly worse than 1.

The other problem is heat. 'Mech Mortar 1 only puts 1 heat, but 2 puts 2, 4 puts 5, and 8 puts 10! Unlike LRM, more tube cause you to raise more heat.

[GreekFire]

Alright, I'll defend 'Mech Mortars, but with certain caveats.

Caveat #1: 'Mech Mortars are a weapon for combined arms play. They are at their best when used on vehicles, against vehicles, battle armor, of infantry. If you only play 'Mech on 'Mech games, they aren't a weapon for you.

Caveat #2: Standard AP Rounds should be avoided. Airburst should be your go-to round unless you're using Semi-Guided shenanigans.

With that said...

Advantage #1: Mortars w/ Airburst ignore movement modifiers and any Stealth or terrain to-hit bonuses, making them well-equipped for taking out stealthy battle armor in entrenched positions at range or getting valuable motive system hits on vehicles. Note that if they hit the hex they're shooting at, they always deal their full damage, so that Mortar-8 doesn't wont need roll to see how many land.

Advantage #2: Airburst rounds are considered AoE weapons, and therefore are excel at removing infantry or battle armor from the table. They also destroy wooded hexes and building faster because of the nature of their damage, which does have its situational uses.

Advantage #3: Airburst Mortar rounds are one of the few AoE weapons that don't drift when they miss, meaning that you can continue firing rounds onto an entrenched position even if you have your own vehicles/infantry in the area.

Advantage #4: This is more of a meta advantage, but Mortars are incredibly cheap in BV. a 'Mech Mortar-8 costs 50 BV, while an LRM-10 costs 90. A ton of Mortar ammunition, 7.2 BV. A ton of LRM-10 ammo, 11. This makes 'Mech Mortars one of the cheapest ways to bring indirect AoE damage to the table.

This also applies to Semi-Guided munitions. If you plan on bringing, say, an LRM Carrier with Semi-Guided rounds in the hopes of using it to park and opponent's vehicles, bringing a Mortar Carrier instead gives you more motive hits at the same range for over less BV.

And since they're so cheap, you can bring something like the Flatbed Truck (Mortar) for 65 BV and use it for specialty munitions - Smoke Mortars being the most useful. As Smoke Mortars *do* benefit from the immobile target to-hit bonus from targeting a hex, and can shoot indirectly at all times even without a spotter, the weapon is probably one of the best ways to reliable create Heavy Smoke hexes for allied units.

[GreekFire]

I'd like to use these, but nobody ever gave me a straight answer for or examples in game terms w/ t/h calculations.  Plus errata, apparently.  Too bad.

When fired indirectly, the suffer from a +1 to-hit along with any spotter modifiers (+2 to-hit if no spotter, +2 to-hit if the spotter ran/flanked, +1 to-hit if the spotter walked/cruised). All other modifiers (range/terrain/attacker+target movement) apply normally for Armor Piercing and Anti-Personnel rounds. They can also be fired directly, but suffer from a +3 to-hit - as the weapon can be fired indirectly even when line of sight isn't completely blocked, there's no real reason to ever shoot them directly.

Airburst rounds target hexes, so ignore terrain and target movement - but do NOT gain the -4 to-hit bonus for targeting an immobile hex.

Smoke and Flare rounds target hexes, so ignore terrain modifiers - and DO gain the -4 to-hit bonus for targeting an immobile hex.

Semi-Guided rounds work like Semi-Guided LRMs, with the same to-hit numbers.

--------------------

EXAMPLE 1: Armor Piercing Rounds at Medium Range, against a target that has moved 3 hexes into some light woods.

4 (base gunnery) + 0 (attacker did not move) + 2 (medium range) + 1 (target moved 3 hexes) + 1 (light woods) + 1 (fired indirectly) + 2 (no spotter) = 11 to-hit.
This can drop down to 9 to-hit with a spotter.

- - -

EXAMPLE 2: Airburst Rounds at Medium Range, against a target that has moved 3 hexes into some light woods.

4 (base gunnery) + 0 (attacker did not move) + 2 (medium range) + 0 (ignores woods and movement since we're attacking a hex) + 1 (fired indirectly) + 2 (no spotter) = 9 to-hit.
This can drop down to 7 to-hit with a spotter.

- - -

EXAMPLE 3: Smoke Rounds at Medium range

4 (base gunnery) + 0 (attacker did not move) + 2 (medium range) + 1 (fired indirectly) + 2 (no spotter) - 4 (immobile target) = 5 to-hit.
This can drop down to 3 to-hit with a spotter.

[PuppyLikesLaserPointers]

While it is far heavier, Long Tom Artillery Cannon does it much better, if what you want is indirect AOE attack. But since it can't use smoke or flare, perhaps mortars have a niche.

Also, I think that Mortar 1 can be a good sidearm for the mech. It cause less heat and is small.

[Retry]

Just wait until someone in the IS wises up and develops the first Air-Burst LRM munitions...  >:D

[GreekFire]

While it is far heavier, Long Tom Artillery Cannon does it much better, if what you want is indirect AOE attack. But since it can't use smoke or flare, perhaps mortars have a niche.

Yes and no. While I am a huge supporter and user of Artillery Cannons, sometimes Mortars will fit your force better.

The biggest difference is that Artillery Cannons require spotters in order to shoot indirectly. Mortars do not. This can be a pretty substantial advantage depending on the map, the rules being used, and your force composition.

The Long Tom Cannon has splash and drift, and costs a pretty substantial chunk of BV. Mortars are extremely cheap in BV, and you have complete control over where they'll deal damage.

The Sniper and Thumper Cannons are more affordable, but are more of a close-range alternative while the Mortar remains long-ranged.

So yeah, I'll agree that the Cannons are fantastic weapons for what they can bring to the table, but Mortars offer some additional flexibility for a BV cost that can't be matched.

Just wait until someone in the IS wises up and develops the first Air-Burst LRM munitions...  >:D

Well, like you said, they existed with the old Mine-Clearance Ammo rules that were broken beyond belief.

[Jim1701]

After they erratta'd  the modifiers I tried them a few more games but their performance was so bad I gave up on them.  At least for what I could get from equivalent LRM launchers. 

[Sartris]

when did the eratta take place?

[Empyrus]

And since they're so cheap, you can bring something like the Flatbed Truck (Mortar) for 65 BV and use it for specialty munitions - Smoke Mortars being the most useful. As Smoke Mortars *do* benefit from the immobile target to-hit bonus from targeting a hex, and can shoot indirectly at all times even without a spotter, the weapon is probably one of the best ways to reliable create Heavy Smoke hexes for allied units.

! [metal gear alarmed sound]

I forgot the Flatbed Truck mortar exists! And it even has an incredible mini with mortar option.

A pity it is only 2xMM-1 but whatever, for the price they seem great for smoke support at very least.

[GreekFire]

when did the eratta take place?

They've gone through a few iterations now, but I think the last change was in 2012.
The ammunition of choice, before the errata, was Anti-Personnel. But things haven't changed too much, the general ruleset has stayed the same for a while now.

A pity it is only 2xMM-1 but whatever, for the price they seem great for smoke support at very least.

It's actually great that it's 2x MM-1s. Each Mortar - even just one on its own - will lay down a 2-level plume of Heavy Smoke that last 2 rounds. Super useful, and the fact the smoke dissipates so quickly means that your opponent will be less able to use it even if you have to maneuver out of the smoke. Since they're also rear-mounted, it's pretty easy to get out of dodge a lot faster if you really have to.

If you want sheer mass of Mortar, though, the Mortar Carrier (LRM Carrier variant) is they way to go. 315 BV less than an LRM carrier, same speed, same endurance, double the armor. Less "oomph" in terms of raw damage, but just as dangerous (if not more) against an enemy's conventional forces.

[Empyrus]

Forgot s, meant 2xMM-1s.

As for Mortar Carrier... LRM carrier doesn't look like one. Yes yes, not WYSIWYG but meh. Gonna need a mini that either looks like a bigger mortar carrier than the Flatbed, or get something that can be modded. Another long-term project, just gotta remember it at some point...
Good to know there's a Mortar Carrier though, forgot to check LRM carrier variants.

[Sartris]

They've gone through a few iterations now, but I think the last change was in 2012.
The ammunition of choice, before the errata, was Anti-Personnel. But things haven't changed too much, the general ruleset has stayed the same for a while now.

ah ok. just wanted to make sure there wasn't some recent change. the post 2012 rules are the only ones i've used for mortars

[Colt Ward]

And since they're so cheap, you can bring something like the Flatbed Truck (Mortar) for 65 BV and use it for specialty munitions - Smoke Mortars being the most useful. As Smoke Mortars *do* benefit from the immobile target to-hit bonus from targeting a hex, and can shoot indirectly at all times even without a spotter, the weapon is probably one of the best ways to reliable create Heavy Smoke hexes for allied units.

This got my attention . . . how thick and what spread, type & duration of smoke is it?  It might end up replacing Thumpers as my Smoke choice when it is available.

[Jim1701]

when did the eratta take place?

Airburst Mortars (p. 373)
1) Change the header in the first bar from “Airburst Mortars” to “Airburst Mortars [’Mech Mortar]”
2) ④ Under “Game Rules”, replace the entire entry with the following:
This ruling has changed from previous errata versions.
Airburst Mortars are area-effect weapons that are fired at a hex, rather than at a target unit. Airburst Mortars
inflict 1 damage point per shell to all targets in the hex, and deliver their damage in 1-point clusters (conventional
infantry treat Airburst Mortars as a burst-fire weapon that delivers 1D6 ÷ 2 damage per shell). Only units inside
buildings avoid this damage (though the building itself suffers damage to its CF). Each shell of Airburst Mortar
ammunition inflicts 2 points of damage in an ammunition explosion (multiplied as normal by the mortar rack’s
size and the total number of unfired rounds). Under no circumstances do Airburst Mortars apply the –4 immobile
target to-hit modifier, regardless of whether the target of the attack is a hex, is shut down or immobile, and so
on.

Prior to this errata air burst was an effective deterrent to fast units.  After errata my mortar units just became targets that were destroyed often without being able to score a hit before they died.  Not as bad as standard rounds for hitting a fast unit but with the built in attack modifier penalties, still not good. 

I later switched to dual Thumpers mounted on Demolisher hulls but artillery was eventually banned from the table for being too deadly. 

[Retry]

This got my attention . . . how thick and what spread, type & duration of smoke is it?  It might end up replacing Thumpers as my Smoke choice when it is available.

1 hex thick, 2-level heavy smoke, 1D6 random direction scatter, 2 turns per shell.

[Daryk]

Hmmm... may have to switch to MM-1s from LRM-5s for my smoke needs...  ^-^

[Retry]

Hasn't been worth the hassle or flexibility loss, in my experience.