I've recently created a tool to automate the testing of Weapons vs. Vehicle Targets in Only War. (with Runtime, without Runtime).

I used this tool to create an extensive table of common Anti-Tank Weaponry and typical Imperial Vehicles.
The Table can be found here.
It's currently Work in Progress but the Front Facing hits are all done. Due to its sice I won't post the table in the forum but once I'm completly done I might pick out some interesting results and talk about them.

Edit: Sorry about double posting. This one's the real thread.

Temporary Verdict: Increasing the Penetration of AT Weapons or decreasing the Armor of Tanks would greatly help to get some reasonable Hits per Kill.
For example the Multi Melta takes on average 9 rounds to destroy a Chimera if fired at the Front Facing. If one would double the penetration by moving closer it only takes 2.8 rounds.
In general it seems like the problem is not so much the weapons themselves (since 3 hits against a Chimera is in my opinion acceptable to destroy it) but the fact that especially the tanks are far to tough.
For example if you were to shoot at a Leman Russ Battle Tanks front Armour with a Missile Launcher and Krak Missiles you'd need roughly 70.000 hits to destroy it. Assuming you hit 3 out of 4 shots and the weapon magically reloads instantly that's 6 1/2 days of continous fire.

Based on what I see in the Data (though this is based on "feeling" the data rather than evaluating it in detail) I feel like the following changes would be easy to implement and make imperial vehicles less indestructible:

-Reduce SI by some amount

-Reduce Rear armour by a miniscule amount

-Reduce Side armour by a small amount

-Reduce Front armour by some amount

This is of course more a general guideline than a solution that can be applied to all imperial vehicles. Especially the Leman Russ Battle Tank and its variants are are far to tough and can stand dozens of hits of all but the most powerful Anti-Tank Weapons and even survive more than a few of those…and that is before "Jink!"

As an example the Leman Russ Demolisher can take about 5 hits of highly accurate Vanquisher Rounds (assuming to have hit with 5 DoS to increase the damage by 2d10) even if they all hit the weakest spot (the rear).

 I've been noticing this trend with vehicles in each subsequent release for 40k. I think that reducing armour isn't necessarily the way to go, but massively reducing the structural integrity of all vehicles is. Armour should be the number that determines how tough a vehicle is, as SI should more be indicative of it's size - for example you could have a large civilian truck or similar that has the same SI as a Leman Russ, but of course isn't going to have much better armour than Carapace or Power armour. Conversely a Sentinel scout walker will have similar armour to a civilian bike, but will have more SI as it is bulkier.

Kasatka said:

You may be right about that one. A few points in armour however need to go I think. If you look at the table you'll notice quite a lof of "Can't damage" and really high numbers of HtK (like 50 to 100+). Those are often times cases of powerful weapons simply doing no damage unless max damage or nearly max damage is rolled so the only way of destroying the vehicles is by plinking it to death, a few points of SI at a time.
Even if you were to reduce SI by 50% that would only reduce the time it takes to plink a target to death by, well 50%. Decreasing the armour by only 1 or 2 points however would have the same effect.

Anyway I seriously hope that FFG takes a look at this (or at least at their own testing of vehicles) and gives them at least a little do-over. I can propose changes as much as I want or even create house rules for vehicle stats but I'd much rather have an official (and hopefully more elegant) solution to the whole problem.

Musclewizard said:

Aye, even a 10% reduction in LR and variant Armour ratings would be sufficient, in addition to (for arguments sake) a universal -50% SI. As per your table and the 'Can't damage' results, i'm fine with multilasers not hurting vehicles (beyond the open topped sentinels) and Baneblades being immune to anything but the largest ordnance and anti-take explosives.

Kasatka said:

One other question - should the '0-is-critical' stay in for vehicles?

On the one hand, no amount of plinking with las-fire should take out a tank, but on the other, a heavy bolter shell or autocannon slug should still be able to mess up a track or gun barrel, even if it can't go through the main armour belt…

Magnus Grendel said:

Actually, I did a reread on this last night, as far as I can tell, vehicles actually don't take one point of damage if a 10 is rolled on the attack, but still failed to surpass armour.

Could be wrong though.

no, that's correct.

Righteous Fury as a whole got a bit of a kneecapping in the damage department. Against creatures, you deal one point of damage if you would not have otherwise, but if even one damage got through from your actual result, you instead cause a 1d5 non-stacking mini-crit. They're nice, they can be quite handy, but its a minor debilitation if you're lucky, rather than "its dead that much faster".

Against vehicles, IF, and only IF, you get through the armor to deal integrity damage, and you roll a ten, then you're also causing one of those 1d5 mini-crits to a part of it. This can be extremely lethal to skimmers, fliers and the such, but is otherwise rather unremarkable.

It's actually quite important that RF does NOT deal at least 1 point of damage to vehicles
If it would 2400 Guardsman coulld destroy a Baneblade in 6 seconds.
2400 Guards with BS 35, half action aim and single shot gives effective BS of 55. So of 2400 Guardsman ~1200 hit. Out of 1200 Guardsman one in 10 rolls a 10 -> 120 Damage to the Baneblade.

 By the way, what armor facing are you targeting with these calculations? Because before vehicles got massively nerfed in 6th ed, a Leman Russ could easily take more than a dozen krak missiles to its front armour without going down. If a squad tackles a tank without flanking it they're doing something very wrong.

Also, people always seem to forget to add size bonuses in their to-hit calculations. Firing at an Enormous vehicle gives a +30 to hit, which makes the Vanquisher extremely deadly. 

then again, maybe that many should.

2400 guardsmen, at BS 35, half-action aim, normal range, using semi-auto [three shot burst]:

55% of them miss

20% of them strike once:  480 hits

20% of them strike twice: 960 hits

5% of them strike thrice: 360 hits

A total of 1800 directed energy pulses strike the vehicle over six seconds. Even dispersed across the armor, it greatly interferes with energy distribution due to multiple heating zones. In a single volley, the super-heavy vehicle has suffered almost two thousand hits.

Perhaps it wouldn't be out of line to offer that one point of damage IF the RF result would at least reach half the damn thing's Armor rating?

Wouldn't help those guardsmen against the baneblade, but the back-end of a leman russ? That's gotta at least cause some bloody heating.

JuankiMan said:

There's 3 categories at the bottom. So I actually did the calculations for all 3 facings. I also ignored size and other to-hit bonuses in my calculation (the google docs one I mean) because I assumed 100% to-hit chance. After all I was interested in the Hits per Kill not the Rounds per Kill since the latter is modified by firing rate, degrees of sucess, dodging ("Jink!"), size, ammo capacitity and reload speed. Better to recude variables I think.
If you're talking about the Guardsman example you are of course correct but the point still stands. If you allow RF to deal always at least one point in damage every target could be destroyed if you apply enough shots.

@Kiton

Adding some special clause under what condition an RF hit should still deal one point of damage would be cluncky while serving little purpose of actually benefiting the game. Wether or not a large number of weak attacks should be able to damage a strong target (they shouldn't just replace lasguns with stones and the result would be the same) is such an edge case that it doesn't need a specific clause to handle it.

Accurate is still limited to +2d10 which cannot initiate RF. Beyond maximizing the individual hit's dice, it does not change the minimum roll of 20 on those 5d10+10 Pen 16 hits required to cause a single point of structural integrity against the front of a Russ. With the average roll being 27.5, and 19 or less doing nothing, the low damage and high number of shots required by a vanquisher cannon were already taking full-accuracy hits into account.

Its being generous towards the weapon, but ignoring straight hits, misses and +1d10s outright assuming all damage checks are on the full 5d10+10 is still leaving the thing quite short of 'tank destroyer'.

I'm in favour of RF damaging tanks and any other vehicles, but also in favour of AT weapons being damaging to most tanks. We've added +2d10 to most of them in my game (leftover from DH plasma weapons being sucky) but i realise this might not suit all. Pherhaps the devastating weapon trait could reduce the armor by X points per degree of devastating, or you could give them a trait that doubled their damage against any target with a TB/ARMOR value above a certain amount, i.e. space marines, carnifexs and Vechiles. this would represent the rather gross overpenetration of AT weapons against a normal trooper.