20mm vs Thin Skinned Targets - A request

[Jarmo]

Originally posted by ASL Veteran:

I would be curious to know if the blast rating of six is the blast rating for just one round or if the blast rating represents the blast effects of multiple rounds.

It's for the whole burst. Dunno how many shots that's supposed to be.

[ASL Veteran]

Let me rephrase that ... are they calculating the effect of a whole burst based upon the blast effects of one round? How does the blast rating of 6 rate when compared to other blast ratings? Does it look like one round or more than one round?

[Claymore]

Every burst (4 rounds) from the cannon has a total BLAST = 6.

[ASL Veteran]

Originally posted by Claymore:

Every burst (4 rounds) from the cannon has a total BLAST = 6.

So that would mean that the individual rounds would each have a blast rating of 1.5. Does this look correct for a 20mm? What is the blast rating for a 37 or a 50?

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When we were in the Bocage country we were assaulted by them Tigers ... you know what I mean by assaulted huh? WELL I MEAN ASSAULTED!!!!

[Guest Michael emrys]

Originally posted by Pascal DI FOLCO:

Eh eh, this problem had been neatly solved in *not to be named WW 2 tac game* ...

Very small calibers with high ROF are given an Infantry-equivalent Firepower to use "directly" against unarmoured/soft targets, instead of tracking effects on a round by round basis.

This is the suggestion I was about to make. Seems like the right way to go about it.

And the thing about hitting where a moving target was is overdone. You'd think they (the notional gunners modeled in the game) would be able to figure out how to lead a target, don't you? Even make it contingent on experience level.

Michael

[This message has been edited by Michael emrys (edited 02-15-2001).]

[Guest Michael emrys]

Originally posted by tero:

The mortars at least do not accept units as targets..... hence they will not shift fire automatically to keep the target under fire.

In my experience both parts of this statement are false.

Michael

[Guest Michael emrys]

Originally posted by Terence:

I read somewhere that tracer makes your shooting less accurate cause the tracer rounds have different ballistics than the regular rounds. When units had their tracer taken away, their kill rating went up. Ill try to track this down somewhere. But no promises.

I read the same thing in a usenet newsgroup a couple weeks back in relation to 0.50 caliber air-to-air. In the PTO, I think, but have no further details.

Michael

[illo]

And what in world .50cal tracer accuracy has to do with german 20mm AA tracer accuracy???

Why 20mm guns in CM fire only 4round burst and then reload for many seconds. I though that 20mm autocannon had MUCH bigger clip. If they are adjusting aim it should be done while firing anyway.

[Claymore]

ASL Veteran,

From the dim crevices of my memory the FLAK ammo stats were as follows:

(I will check this from home later)

20mm Projectile Weight = 0.13kg

Bursting Charge = 0.06kg

ROF = 120 rnds/min (practical)

37mm Projectile weight = 0.75kg

Bursting Charge = 0.36kg

ROF = 40 rnds/min (practical)

So per round the 37mm will deliver 6 times greater HE to the target than the 20mm, however the 20mm fires 3 times as fast. Overall then that means the 20mm puts only half the HE on target per burst than the 37mm. This is why the Germans switched to the 37mm for FLAK duty. Against fast moving airplanes you need to ensure a 1 round hit/kill. Against the more leisurely movement rates of jeeps and infantry I leave you to make your own conclusions. IMO against infantry and the like the 20mm would be far more effective than MGs or even the 37mm.

As for the historical record, I can only recall Korea, where the 40mm BOFORS was prefered (slightly) over the (non-explosive) Quad 50's in long engagement distance attacks against the Red Horde. Close in (<200m) the mounted 40mms were far less effective.

So...let's take the CM model of the 37mm as the "good baseline" for our comparisions since nobody has ever complained about it (except those on the receiving end)

CM models:

37mm - BLAST = 26

Quad 20mm - BLAST = 26

Single 20mm - BLAST = 6

Going straight from the HE fills and ROF the math predicts:

37mm - BLAST = 26 (benchmark)

Quad 20mm - BLAST = 52

Single 20mm - BLAST = 13

Obviously there is a "fudge" factor in the BLAST ratings that BTS applies to a gun's ratings. Let me say here that I do not think that given the CM model the BLAST ratings should be changed as the math predicts. However, I still cling to the hope that BTS will do something about the impotent 20mm vs infantry and soft-skinned targets.

Waiting by the window...

Throw me a line BTS...let me know what you think.

Cheers

Murray

[Claymore]

A shameless and self serving bump to the top.

Still waiting for any comment by BTS.

The close assault thread at least got a "I'm looking" message. Am I wandering in the desert alone here?

Cheers

murray

[Jarmo]

.50 cal tracers air-to-air.

AFAIK, the kill ratio went up when the planes stopped using tracers.

But this was due to the tracers revealing the position of the firer,

not because they would have different ballistics.

It's easier to see from which direction the fire is coming if

you have a tracer line pointing towards the shooter.

Doesn't mean the ballistics wouldn't differ. Maybe they do.

That's just stuff I heard somewhere...

[John Kettler]

Can anyone supply information on the actual composition of the ammo load for the 20mm flak

gun? Restated, was it all of one type or was it mixed natures, like American .50 caliber MG

ammo? I distinctly recall a program on the History Channel in which Belton Cooper gave

the exact sequence of ammo types in a belt of

.50 caliber ammo. It was something like two rounds of ball, one of AP, one incendiary, one tracer, or some such, then repeat.

Regards,

John Kettler

[Vanir]

Originally posted by Claymore:

Vanir,

Could you please email me your setup?

[address: mrdarrach@skyweb.com]

It's in the mail.

[Claymore]

Bumpity bump

Sending a personal email to Matt now as the Forum discussion has yielded nothing from BTS.

Cheers

Murray

[Vanir]

Ok, Murray. I got your test and tried a few. There were a few things about it that I didn't like. The squads were only veteran instead of elite (longer delay before they start running), starting them out 250m from the gun meant that when you ran them toward the guns they often got close enough to do some casualties, and the MG42s were in houses that protected them while the 20mms were in the open.

So I took your ideas and made my own test and modified the test I sent to you and retried it. I had wondered if maybe I had the squads too close together so that they were running into 20mm fire intended for the squad in front of it. So I double the distance between squads. After running these 2 tests I have come to a conclusion:

You were right. There is something wacked about how the 20mm works.

First, my modified test. This is where 3 squads of elite troops run across the line of fire of 3 regular MG42s/20mm each targeting 1 squad. This is for 1 turn. I made sure there was 80m between each squad to ensure that each gun only hit the squad it was aiming at. After 20 runs each the results were:

MG42: 99 kills, 4.95 per turn.

20mm: 83 kills, 4.15 per turn.

The MG42 produced 19% more casualties than the 20mm.

The second test was similar to the one you sent me. 3 elite squads start out 300m from the 3 guns targeting them and run directly towards them for 1 turn over open terrain. They usually ended the turn about 80-90 meters away from the firing guns. After 20 runs I got the following results:

MG42: 209 kills, 10.45 per turn.

20mm: 97 kills, 4.85 per turn.

The MG42 produced 115% more casualties than the 20mm.

I don't know why the difference is so much greater when running towards than when running across. It probably has something to do with the ranges. In any case, I'm going to send the test with the squads charging towards to MadMatt. Hopefully they can spare a few minutes from testing assaults on halftracks to look at this.

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You've never heard music until you've heard the bleating of a gut-shot cesspooler. -Mark IV

[This message has been edited by Vanir (edited 02-17-2001).]

[Guest Madmatt]

I have looked at both the Close Assualt issue (which we have already said we see nothing wrong with) and this issue and I also don't see anything wrong with it.

You guys apparently have been watching SPR too much. A cannon has MUCH slower ROF and shell velocity than the MG42. There is absolutely nothing wrong with the results here. The blast rating of the 20MM is around the same as that of a grenade and against a fast moving and dodging infantry sized target it is not easy to achieve accurate fire. With a MG you can pretty much spray and pray and still achieve good results. Cannons are good against large targets (vehicle/plane size) and slow moving or stationary concentrations of troops. It also gives a pretty capable anti-armor punch as well as it's intended Anti-Air defense role. You are comparing apples and oranges here.

Your test map is a high rate of fire MG (like the 42's) dream!

Put that infantry in some cover or add a few vehicles to the attacking force. That is a more fair test of each weapons relative strengths.

Madmatt

[Vanir]

Well, I'm no expert on the real world effects of cannons on people, so I will defer to your judgement. Your explanation does make sense. Thanks for the reply

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You've never heard music until you've heard the bleating of a gut-shot cesspooler. -Mark IV

[This message has been edited by Vanir (edited 02-17-2001).]

[Guest Michael emrys]

Originally posted by Madmatt:

The blast rating of the 20MM is around the same as that of a grenade...

That depends on which grenades you are comparing it to and how loosely you want to define 'around'.

I've just been thumbing through Allied Pistols, Rifles and Grenades by Chamberlain and Gander, and from their figures, the average grenade weighed in at about 0.5kg with the range being approx. 0.3-0.75kg. A very conservative estimate of the blasting charge would be 20-25% of the total weight (actually it varied pretty widely depending on the thickness of the casing) which would give a weight of the blasting charge of 0.1kg. Claymore has posted that the blasting charge of the 20mm is only 0.06kg. In other words, only about half as powerful as a grenade.

The splinters from a 20mm are, I expect, on average quite a bit smaller than those of a grenade as well. While having a 20mm explode inside your body would be bad news indeed, having one go off even a foot or two away would probably only result in superficial wounding, as any number of pilots who had one or more go off in their cockpits could attest.

Having a grenade go off near oneself could be survivable too, but was not nearly so sure a thing.

Michael

[This message has been edited by Michael emrys (edited 02-17-2001).]

[Guest Madmatt]

I meant in the game, as in its relative effects against infantry.

Madmatt

[This message has been edited by Madmatt (edited 02-17-2001).]

[Vanir]

I would think the blast rating for the 20mm assumes more than one round impacting since the game does not model the individual shells, just bursts.

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What a bunch of horsecrap. -Steve

[Guest Michael emrys]

I know you did, MM.

I was primarily responding to those posters who have, I think, somewhat inflated expectations about what they should be seeing. Being hit directly by a 20mm could be deadly, but as you have indicated, the low ROF made that less likely against personnel targets compared to what an MG could do against the same target. A near miss from a 20mm, while not exactly anybody's idea of fun, would likely not produce a disabling wound.

On the other hand, the 20mm should be nearly ideal for shooting up soft or lightly armored vehicles, because they are larger targets and a hit is almost guaranteed. And once hit, the explosive charge could do significant damage.

Michael

[John Kettler]

Madmatt,

Though I don't have the combat accounts handy, I have read of even a single German 20mm ripping a platoon apart and stopping a much larger advance cold. This was a U.S. account, by the way, and one thing which stood out was the description of the horrific injuries those shells caused when they hit. This had a profoundly adverse effect on unit morale. As I recall, that unit was starting to emerge from the trees and enter a clearing when hit.

I read another account of an engagement in Cherbourg, I think, where a halftrack mounted 20mm did pretty much the same thing, except during street fighting. Again, not a quad.

Both accounts were unanimous in their description of the shock and horror evoked by the 20mm's macerating and blowing up their buddies.

The above suggests to me that the 20mm had a morale impact associated with its employment which is simply not modeled in CM, but which people still expect. Years ago, when AFV G-2 magazine was around, there was a gory account of a 250/9 recon unit (company size, I think) simply tearing apart and routing a massed Russian infantry regiment during an attack across the snow toward a village. This account was German, but the recipient reaction was the same as the Americans'--shock, horror and dismay.

The reason for this seems to be one of utter unfamiliarity with the weapon's range, power, horrific effects, plus the wholly new sound it made while firing. Madmatt, by typical grunt standards, the 20mm was a gross weapon, one whose bark and bite were both to be feared. Consider, too, that this thing could shoot through what was cover against most weapons, somewhat like what that .50 cal MG did to the wooden house in "Eye of the Needle," only worse.

These seem to be the issues. How you'll address them, I don't know. I'd suggest people start digging through combat accounts.

Regards,

John Kettler

[Guest tero]

>I have looked at both the Close Assualt issue (which we have already said we see nothing wrong with)

So it is OK for a open topped vehicle to survive 100 odd grenades hurled from 20 or so meters, without even losing a tire and becomming immobilized ? Given the abstracted nature of the infantry graphics some of the troops can be much nearer than the said 20 meters.

>and this issue and I also don't see anything wrong with it.

I think the original question was soft skinned vehicle survivability, not purely infantry.

>You guys apparently have been watching SPR too much.

First time I have seen SPR being said to having misrepresented the German forces in a positive manner.

>A cannon has MUCH slower ROF and shell velocity than the MG42.

MG42 slugs do not explode.

>There is absolutely nothing wrong with the results here. The blast rating of the 20MM is around the same as that of a grenade and against a fast moving and dodging infantry sized target it is not easy to achieve accurate fire.

What is the velocity of a handgrenade ? There is something fundamentally wrong in the modelling if the 20mm shell travels at high speed only to magically lose the velocity when it is time for the shell to explode. The fragmens from the 20mm shell should be travelling at explosion + shell speed velocity. That should translate to way bigger damage effect than currently is modelled.

>With a MG you can pretty much spray and pray and still achieve good results. Cannons are good against large targets (vehicle/plane size) and slow moving or stationary concentrations of troops.

Not entirely true.

- Cannon has much greater effective range

- Infantry rushing from cover to cover is modelled and can be done, gunners "guessing" the targets next move is not modelled.

>It also gives a pretty capable anti-armor punch as well as it's intended Anti-Air defense role.

It was designed with dual role capability in mind.

>You are comparing apples and oranges here.

Not really.

>Put that infantry in some cover or add a few vehicles to the attacking force. That is a more fair test of each weapons relative strengths.

By providing cover you introduce factors (like tree burst effect) to the equation that are irrelevant to the effects (or lack thereof) being debated.

[Vanir]

John, a special moral modifier just for the 20mm would be interesting. That is the only way I can think of to address the issue you raised. I have no idea how practical that would be from a programing standpoint but doing a special model for one weapon would open a big can of worms I suspect BTS would rather avoid. The current moral model is based on number of casualties taken which is a hard number. When you start saying that being fired upon with this weapon was more demoralizing than that weapon (outside of casualties taken) you get into a very subjective area. There are plenty of weapons in CM whose effects would often produce shock, horror and dismay. An infantry platoon caught in the open under a 155 VT barrage would likely suffer gross and horrific consequences in very short order, so shouldn't the 155 VT also have such modifier?

I'm sure others could come forward with similar examples. Eventually it would grow to where many other weapons had modifiers and then you basically have a new moral system within the game. Personally, I think the current system works pretty well.

Try setting up an infantry platoon (regular quality) 700m from a 20mm and see how many minutes (turns) it takes for the infantry to rout. Seems fairly realistic to me.

Originally posted by tero:

What is the velocity of a handgrenade ? There is something fundamentally wrong in the modelling if the 20mm shell travels at high speed only to magically lose the velocity when it is time for the shell to explode. The fragmens from the 20mm shell should be travelling at explosion + shell speed velocity. That should translate to way bigger damage effect than currently is modelled.

The velocity of the 20mm shell has another effect you are ignoring. While grenade fragments will tend to fly in all directions more or less equally, the 20mm fragments will travel in a more or less elliptical pattern away from the point of impact on the shell's axis of travel. This means a soldier standing between the gun and the impact, or directly to the side of the impact, would have a far lower chance of injury than with a grenade in the same situation.

- Cannon has much greater effective range

My tests have shown that the effectiveness of the 20mm vs. MG42 does indeed go up the greater the range of the test. The test I sent to Madmatt was very short range (80-300m).

- Infantry rushing from cover to cover is modelled and can be done, gunners "guessing" the targets next move is not modelled.

I think you are correct that "prediction shots" are not modeled per se. However, there must be some allowance currently made for this in the game or it would be impossible to hit a moving vehicle, for example. I would think that true prediction firing as you suggest would require a major overhaul of the TacAI and gunnery models in the game and is probably not feasible for the near future, at least.

By providing cover you introduce factors (like tree burst effect) to the equation that are irrelevant to the effects (or lack thereof) being debated.

Not really. 20mm shells do not receive tree burst effects in the game (only artillery does this AFAIK). Nevertheless, 20mm is more effective than MG42 vs. stationary targets whether they are in cover or not, especially at long ranges.

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What a bunch of horsecrap. -Steve

[This message has been edited by Vanir (edited 02-18-2001).]

[Guest Madmatt]

The key here is in the rate of fire and distance between men in a squad being engaged.

A MG42 can spit out literally hundreds of rounds in a few seconds (based on between 1200-1500 rounds per minute cyclic rate) while the 20mm is only getting at best a little under 1/2 that amount (assuming between 350-700 rpm and IIRC they aren't firing anywhere near that rate in the game for the most part). While the cannon rounds explode it is doubtful that a single rounds explosion would injure more than one man in a squad using proper combat spread. Obviously a cannon shell will cause greater damage to the target but the end result in the game is same, an incapcitated man.

So, all things being equal, in the same stretch of time the MG42 is able throw out at least twice the firepower and as such cover a greater area with lead with relatively the same effect as the cannon when a man is hit.

A more fair test would be to compare the results based on similar amounts of rounds fired.

The test above shows a MG42 getting 110% more hits than the slower firing 20mm yet what no one is looking at is that both weapons are shredding the squads apart.

Is a MG42 more effective than a 20mm on a one to one basis? In some situations yes, as it was historically.

A cannon will show its greater effectiveness when used against targets in cover over a Machinegun where its inherent, albeit still small, explosive ability come more into play. As I indicated above, add in its anti-armor ability and air defense capability and you have a well rounded weapon.

The direct comparission is apples and oranges as you are taking two different weapon designs with two different intended methods of employment into an artificial situation that greatly favors the overwhelming rate of fire of the Mg42.

As to the effectiveness against light skinned vehicles (jeeps trucks etc..) I decided to conduct a little test with a single 20mm gun setup against a convoy of jeeps and trucks between 300-400 meters away. Within 3 minutes all the trucks and jeeps were destroyed, burning or abandoned.

Much of the Close Assualt issue is peoples incorrect perception of what is happening. True close assaults in the game only occur within 10 meters of the target. Get that close and see how successful your assaults are. At longer ranges than that your squads are trying to do what they can with grenades which are not very accurate themselves and need a decent bit of luck to explode near enough (or under or into) a vehcile to cause suffecient damage to take it out.

Madmatt

[This message has been edited by Madmatt (edited 02-18-2001).]