Minengeschoss

[MK_RED13]

Is the minengeschoss ammo modeled in the game?

[Charon]

I'm pretty sure it is. It's possibly overmodeled, although I don't have hard data to back this up. Shells with a high ratio of explosive filler are very noticeably more effective. Contrast the behavior of 37x198mm HE with 30x90RB:
 

Spoiler

 

[Yogiflight]

I don't know, if this was changed meanwhile, but a few years ago Jason explained, that Minengeschosse are not modelled the way they worked, for the simple reason, that they can't model the effects of the blast inside the aircrafts, so they increased the number and velocity of shrapnels for the Minengeschosse to give them higher effectivity.

[Roland_HUNter]

Funny, the Ju-87 loses his tail after 2 MK-108, but other planes like LA-5, Tempest etc. can hold against 4-6 and still no tail cut off.

IL-2 mod 42 loses his tail after 4 MK-108.
Even the Spit IX with narrow tail section can withstand 5 MK-108.

[the_emperor]

9 hours ago, Yogiflight said:

that Minengeschosse are not modelled the way they worked, for the simple reason, that they can't model the effects of the blast inside the aircrafts

Yes, the delay action is missing. 
Iam not sure but isnt some somewhere in the game files the ammount of HE filling readable?

[the_emperor]

for comparison:

British/US:

5.44g Tetryl R.E. factor 1.25 ~6.8g TNT

(Later) Soviet:

5.6g A-IX-2 (73% RDX, 23% aluminum powder, phlegmatized with 4% wax; R.E. factor 1.54)~8,624g TNT

German:

18,6g HA41 (75% RDX, 20% aluminum powder, phlegmatized with 5% wax; R.E. factor ~1.54)~28.644g TNT

 

[LukeFF]

Guys, if you are going make claims about ammo not performing as it should, upload tracks showing the problem. Otherwise this thread is going to be locked. 

[Charon]

Note that I did upload tracks when I first shared that video:

 

https://user.fm/files/v2-d48e1c12605e5fcba429bcf301cdbdc3/37mm tests.zip

 

[LukeFF]

5 minutes ago, Charon said:

Note that I did upload tracks when I first shared that video:

 

https://user.fm/files/v2-d48e1c12605e5fcba429bcf301cdbdc3/37mm tests.zip

 

 

Thanks ?

[=MERCS=JenkemJunkie]

If you use UnGTP you can find the projectile files in data\(null)\luascripts\worldobjects\ballistics\projectiles, and the HE explosion files in 

data\(null)\luascripts\worldobjects\explosions\heprojectiles.

 

The 151 20mm's have much more explosive power at 0.02 TNT equivalent vs 0.0113 for the Hispanos, and 0.0026 for the ShVAKs. 

 

All the HE bullets (and bombs and rockets) use the same shrapnel shard mechanic mentioned earlier, but with different values for different bullets. There's a small amount of base damage where the projectile hits, and then the majority of the damage comes from many RNG shrapnel shards that hit whatever they hit within a certain range. A lot of the inconsistencies you'll see come down to good or bad RNG. I like to visualize the HE bullets as RNG grenades that I lob at the plane, and when I unload into a plane to not much effect, or if a plane gets deleted instantly I just chalk it up to good or bad RNG. 

 

In addition to bad RNG a lot of the common red planes like the Yak, 51, Tempest are very tanky, and the 109 can be squishy with the easily damaged wings, which can give the illusion that the German 20's are weaker as well, but really the red planes are stronger than the 109. The 190 and 110 can also be tanky. 

[the_emperor]

On 3/12/2024 at 10:16 PM, =MERCS=JenkemJunkie said:

The 151 20mm's have much more explosive power at 0.02 TNT equivalent vs 0.0113 for the Hispanos, and 0.0026 for the ShVAKs. 

Thx @=MERCS=JenkemJunkie

 

sooo those number look a bit off. 

for comparison:

 

British/US:

5.6g Tetryl R.E. factor 1.25 ~7g TNT

 

(Later) Soviet:

5.6g A-IX-2 (73% RDX, 23% aluminum powder, phlegmatized with 4% wax; R.E. factor 1.54)~8,624g TNT

or 4.13g (~6.36g TNT)  for the tracer version

though earlier soviet HE-I rounds held about 2,8g of tetryl (~3.5g TNT) or 2.64g A-IX-2 (~4.07g TNT)

 

German:

18,6g HA41 (75% RDX, 20% aluminum powder, phlegmatized with 5% wax; R.E. factor ~1.5)~28g TNT

 

 

Edited March 22, 2024 by the_emperor

[=MERCS=JenkemJunkie]

Both numbers can't be right, so I guess just give it the usual spam sources and wait.

[the_emperor]

On 3/13/2024 at 2:19 PM, =MERCS=JenkemJunkie said:

Both numbers can't be right

Which numbers?

[=MERCS=JenkemJunkie]

The ones you posted and the in-game ones. One set has to be wrong, or they're for different versions of the round.

[the_emperor]

15 minutes ago, =MERCS=JenkemJunkie said:

The ones you posted and the in-game ones. One set has to be wrong, or they're for different versions of the round.

mine come straight from the manuals and are well known. 

Granted the RE factor I did take from the Wikipedia. 

But that would be a error in the game

Edited March 21, 2024 by the_emperor

[=MERCS=JenkemJunkie]

Maybe, the in-game Sh**VAK rounds are suspect in particular. Why even bother making the round HE if you're gonna put so little explosive material in there.

[the_emperor]

Yes, at least the later Shvak rounds should hold  more TNT equivalent. 
while the Hispano round kept the same amount of HE filling throughout the war and should be decreased and the mineshell increased. 
 

Edited March 21, 2024 by the_emperor

[=MERCS=JenkemJunkie]

Can you post the original sources for that?

 

A quick wiki search tells me the ShVAKs had HE-Frag with 6.7g of HE powder (way stronger than the in-game version), the Hispanos used between 6-11g of HE powder (I guess they used the upper value), and the 151s had multiple versions with varying amounts of powder. Maybe some changes could be successfully argued for, but not based on wiki, or copy/pasted text. They're not doing anything without the original sources. 

 

 

[the_emperor]

9 hours ago, =MERCS=JenkemJunkie said:

Can you post the original sources for that?

for the mineshell you can find those values in every luftwaffe ammunition handbook. 

and for the Hispano, there was only ever a HE-I round for the US/Brits and luckily I did a deep dive into this already and created a whole thread? 

~5.5g of tetryl is the HE filling. (you can find also the HE-filling for the mineshell in this thread)

 

as for the Shvak...finding manuals with the filling weights is hard, but there a fantastic book about soviet aircraft cannons:

 

5.6g A-IX-2 without tracer and 4.13g A-IX-2 with tracer

 

 

from a 1943 manual showing the AP-I and HE-I (~2.8g of HE filling) round:

 

 

 

Edited March 22, 2024 by the_emperor

[the_emperor]

Hence why I would say, that the HE fillings in game should at least be reviewed:

 

British/US:

5.6g Tetryl R.E. factor 1.25 ~7g TNT

 

(Later) Soviet:

5.6g A-IX-2 (73% RDX, 23% aluminum powder, phlegmatized with 4% wax; R.E. factor 1.54)~8,624g TNT

or 4.13g (~6.36g TNT)  for the tracer version

though earlier soviet HE-I rounds held about 2,8g of tetryl (~3.5g TNT) or 2.64g A-IX-2 (~4.07g TNT)

 

German:

18,6g HA41 (75% RDX, 20% aluminum powder, phlegmatized with 5% wax; R.E. factor ~1.5)~28g TNT

Edited March 22, 2024 by the_emperor

[=MERCS=JenkemJunkie]

Be careful what you wish for, so much reading...?.

 

I'm not sure if they converted their in-game numbers to TNT equivalent like it's noted as, they seem to have just used the raw weight of the powder?

 

Also they seem to just be completely ignoring the incendiary component in their damage calculation since they can't model incendiary rounds in this engine. Since they added extra power to the mine shells to make up for not being to sim the round detonating inside the plane, then they should also add some extra power to the HEI rounds to compensate for the missing incendiary component.

 

Assuming they're using the raw numbers instead of TNT equivalent, it looks like they used the ShVAK 20x99R data in the picture you linked with 2.6g of explosive powder, and 2.8 g of incendiary. The in-game value of 0.0026 kg shows they just used the raw number of 2.6g of explosive powder and did nothing for the incendiary component. Later ShVAK rounds should be even stronger.

 

The incendiary component should also be compensated for the Hispanos as well. The newer rounds used (0.012 lbs) ~5.5g of explosive powder, but also (0.005 lbs) ~2.25g of incendiary powder. Looks like they used the raw value of the older round of (0.025 lbs) ~11.3g to get the in-game value of 0.0113 kg. I couldn't find any info on when they switched from the older stronger round, to the newer one though.

 

For the 151, it looks like they chose to only model the 20g version, and again used the raw number of 20g (0.02 kg in-game value) in-game instead of converting to TNT equivalent as noted in the files.

 

 

[the_emperor]

7 hours ago, =MERCS=JenkemJunkie said:

then they should also add some extra power to the HEI rounds to compensate for the missing incendiary component

if you do that you would also have to add additional "destructive power" to the soviet and german shells as their modern filling has also very good incendiary characteristics...

the german even more due to the delay action...

So as long as you cant simulate the incendiary properties one should stick to simulate what you can and by the right historical number. 

 

[=MERCS=JenkemJunkie]

2 hours ago, the_emperor said:

if you do that you would also have to add additional "destructive power" to the soviet and german shells as their modern filling has also very good incendiary characteristics...

the german even more due to the delay action...

Sounds good to me, I'd prefer that to just not adding the I in HEI at all.

2 hours ago, the_emperor said:

So as long as you cant simulate the incendiary properties one should stick to simulate what you can and by the right historical number. 

If you believe that, then you should also believe that they should remove the extra power from the mine shells that they added to compensate for not being able to have them detonate the historical way. If they already set the precedent by increasing the mine shells shrapnel amount and velocity, then they should also compensate for no I in HEI.

[the_emperor]

the mineshell is indeed a tricky one as most shrapnel is produced by the airframe it hits and some very small fast fragments of the of the shell (and some bigger of the fuze but nothing compared to the Hispanos 130g slug).

My take would by to reduce the shrapnel part and compensate for structural and surface damage (e.g. when a wing is hit you will have a big hole on both sides of the wing surface simulating the round going off inside the wing and blasting away from the inside out in contrast to others going off on the surface and the pressure effect weakening the internal structure).

But again it is a very difficult question on how to "simulate" that round within the limits of game, and compensate for the missing incendiary components (for all nations).

But we can agree that the Shvack 20mm round seems to hold a bit to few explosive according to the game files.

Edited March 23, 2024 by the_emperor

[=MERCS=JenkemJunkie]

I'd like that idea, it would be interesting to see if the damage model becomes less frustrating and have less weird moments if they shifted damage away from the RNG shrapnel shells and more into the base damage.

The Sh**VAK needs love, anyone complaining about Russian bias can just take one look at the ShVAK to dispell that.

[FeuerFliegen]

Can anyone tell me what the German 20mm FF/M had regarding explosive content, compared to the MG151/20?

 

I was talking with someone the other day and he told me he was watching a video that stated that the 20mm FF/M had more explosive filler than the MG151/20.  I was completely unaware of this, but he couldn't remember who made the video or where to find it, so if anyone could tell give me the figures for the two, it would be much appreciated.

Edited March 30, 2024 by FeuerFliegen

[the_emperor]

On 3/30/2024 at 8:38 AM, FeuerFliegen said:

20mm FF/M

The "M" stands for Minengeschoss.

And the 20mm FF had to be adjusted to fire the lighter 92g shell instead of the normal 115g shell. 

Filling weight was the same but earlier held tetryl/petn he filler (visible by black explosive cloud instead of white bright blast)

Edited April 4, 2024 by the_emperor

[FeuerFliegen]

On 3/30/2024 at 6:36 AM, the_emperor said:

The "M" stands for Minengeschoss.

And the 20mm FF had to be adjusted to fire the lighter 92g shell instead of the normal 115g shell. 

Filling weight was the same but earlier held tetryl/petn (visible by black explosive cloud instead of white)

 

Right; I've read about the differences between the MG FF vs the MG FF/M and how they had to be careful not to mix the ammunition, but my question is regarding the difference in HE filler between the MG FF/M and the newer MG 151/20

[Roland_HUNter]

On 3/12/2024 at 10:12 AM, the_emperor said:

for comparison:

British/US:

5.44g Tetryl R.E. factor 1.25 ~6.8g TNT

(Later) Soviet:

5.6g A-IX-2 (73% RDX, 23% aluminum powder, phlegmatized with 4% wax; R.E. factor 1.54)~8,624g TNT

German:

18,6g HA41 (75% RDX, 20% aluminum powder, phlegmatized with 5% wax; R.E. factor ~1.54)~28.644g TNT

 

Late HEF (High-Explosive Fragmentation) ammo had ~4 g of explosive in it.
Only the late FI (Fragmentation Incendiary) ammo had 5.6g of explosive.

[=MERCS=JenkemJunkie]

They were previously using an HEI round as well for the early version, so using a late round with an incendiary component as well would be consistent for them. This round linked above though has 5.6 of filler and weighs 96g, which matches the version 1C used, so thats a likely candidate for the version 1C chose.

 

[Roland_HUNter]

Other:
I could cut the Hurricane wing with ~12 HE Shvak.

This is 25 HE, Minen:

 

Please test this, and tell me, this is just a mistake by me, not a real thing.

[=MERCS=JenkemJunkie]

There's so many variables in the damage model like where the bullets hit, where the shrapnel shards hit and how many, and what those hits register as that seeing weird results in testing doesn't surprise me.

I'll post the code for the explosions, and you can see for yourself which shell has a stronger explosion with the objective numbers. The only area where the ShVAK has an advantage is in the mass of the shrapnel shards, but the 151 shards are faster, and more numerous, and end up doing more damage at all times anyways. I tried to color code to make it easier to follow, but if you want to TLDR it, all you really need to know is the 151 numbers are bigger.

I also looked up the projectile damage that the bullets do, and they're very similar at closer ranges, with the ShVAK doing a little more damage at longer ranges.

[the_emperor]

@=MERCS=JenkemJunkie

thanks.

could you also put up the file for the british/us 20mm Hispano system?

Many Thanks

[=MERCS=JenkemJunkie]

There's also a separate file for the projectile damage, and the Hispano has much better projectile (should have same effect an AP round would do) damage than the other two, especially at longer ranges.

[Avimimus]

That makes sense - the Hispano round is much heavier (168g vs. 96g for the ShVAK)... 

[the_emperor]

1 hour ago, Avimimus said:

the Hispano round is much heavier (168g

131g. but yes. its the heaviest of all 20mm rounds

[=MERCS=JenkemJunkie]

The numbers don't lie, so believe it or not, it's still the best 20mm of the 3, not counting the Hispano doing more projectile (AP) damage.

[the_emperor]

though I am very happy that the later soviet 96g shell git introduced.

It muzzle velocity is rated at 800m/s (not 840m/s), it countains 18g of propellant instead of earlier 19.2g for the 91g shell

 

[the_emperor]

here the muzzle velocity is 

815m/s for the 91g shell with 19.2g of propellant weight and the long 1540mm motor canon barrel

 

while the heavier bullet had less propellant (18g) probably to keep the chamber pressure the same (as it was the case with the german mineshell which was lighter than the common shell and usually had a bit more propellant)

 

so putting the later 96g shell at a mv of 840m/s would probably exceed the chamber pressure of 3000kg/cm2

[Roland_HUNter]

On 4/17/2024 at 9:25 PM, Roland_HUNter said:

Other:
I could cut the Hurricane wing with ~12 HE Shvak.

This is 25 HE, Minen:

 

Please test this, and tell me, this is just a mistake by me, not a real thing.

This video says by US trials, that 17 MG 151 and 4 Mk108 destroyed a B-17.
Hurricane wing can stand 6-8 MK108...