.50 cal damage, or lack there of

[ACG_Cass]

http://www.quarryhs.co.uk/WW2guneffect.htm

 

Have just stumbled across this. A lot of assumptions in there, but still, some solid maths around it that I could see being used as a guide on building a Damage Model. 

[HR_Zunzun]

1 hour ago, JG7_X-Man said:

 LOL So you agree with me - that is 1% = 1/100 = 1 in 100  = 1:100 chance of not rendering an aircraft combat ineffective.

Yes, that is exactly what i meant. Glad you find it amusing too ?

[unreasonable]

14 hours ago, SAS_Storebror said:

 

1. What's more effective? 2 Fragments of 7.1 grams each, or 5 fragments of 3 grams each? Why the difference? Source?

Mike

 

The total weight in each shell is about the same, but the German shell contains a much lower ratio of HE/metal. This will tend to make the German shell produce fewer splinters, each with a lower initial velocity. 

 

See table one on this page - this is about artillery shells but the principles are the same: higher explosive ratio > more splinters at higher velocity, cet par. 

 

http://nigelef.tripod.com/wt_of_fire.htm

 

As to which is better: the total energy contained in the splinters is k=mv^2, so 2*0.0071*342^2 = 1660.89  vs 5*0.003*535^2 = 4293.38

 

If you divide that by the TNT equivalent weight you get very similar j/kg in each case so the calculation look consistent.

 

So it is a similar question to whether you are better off having one .50 cal AP hit vs some number of 303 hits: it depends what you hit. Smaller fragments are more likely to be stopped and transfer all of their energy to the target, but larger ones will tend to get through skin and light armour better. 

 

Speculating, I suspect that there is only one value for the ArmorFoug lines because the blast effect is not supposed to affect anything behind armour thicker than a certain quantity.

 

 As for  

ArmorFoug = 0.5, -1, 0.140

 

I would check that to see if there is a decimal place error and it should be 1.400 - then the ratio of the values in the lines would be very similar in each case. 

[SAS_Storebror]

1 hour ago, unreasonable said:

Speculating, I suspect that there is only one value for the ArmorFoug lines because the blast effect is not supposed to affect anything behind armour thicker than a certain quantity.

 

 As for  

ArmorFoug = 0.5, -1, 0.140

 

I would check that to see if there is a decimal place error and it should be 1.400 - then the ratio of the values in the lines would be very similar in each case. 

 

Actually it turns out that the dot separates the elements of a pair.

German 13mm:

// High-explosive effect: range, (-1 not used), pairs (armor, damage for armor)
ArmorFoug = 0.0, -1, 0.257
ArmorFoug = 0.5, -1, 0.83
ArmorFoug = 0.6, -1, 0.65
ArmorFoug = 0.7, -1, 0.50

Means:

At touch distance (0.0m), the shell does damage if the part/skin is unarmored only (0 in front of the dot), and in that case the damage value is 257.

At 0.5m distance, same rules apply, damage decreases to 83.

At 0.6m damage decreases to 65.

At 0.7m damage decreases to 50.

No HE explosion damage beyond 0.7m distance.

 

Russian 12.7mm:

// High-explosive effect: range, (-1 not used), pairs (armor, damage for armor)
ArmorFoug = 0.0, -1, 0.453
ArmorFoug = 0.5, -1, 0.140
ArmorFoug = 0.7, -1, 0.83
ArmorFoug = 0.9, -1, 0.50

Similar to german 13mm round, but higher values everywhere. Again, no damage to armored parts from HE blast.

HE damage at touch distance: 453.

At 0.5m: 140

At 0.7m: 83

At 0.9m: 50

No HE explosion damage beyond 0.9m distance.

 

The Format for the fragments is a bit odd. The first dot is a decimal dot, all other dots separate elements of pairs.

German 13mm:

// Single shard: range, speed, pairs (armor, damage beyond armor)
ArmorShr = 0.0.342, 1.42, 0.167
ArmorShr = 1.3.336, 1.40, 0.161

Means:

At touch distance (0.0m) the shrapnel speed is 342 m/s, and it can do damage to level 1 armored parts with damage value 42, and to unarmored parts with damage value 167.

At 1.3m distance the shrapnel speed is 336 m/s, and the damage values are 40 (armor level 1) and 161 (unarmored).

No shrapnel damage beyond 1.3m distance apparently.

 

Russian 12.7mm:

// Single shard: range, speed, pairs (armor, damage beyond armor)
ArmorShr = 0.0.535, 2.42, 1.106, 0.169
ArmorShr = 2.0.509, 2.38, 1.96, 0.153

At touch distance shrapnel speed is 535 m/s, damage values are 42 (armor level 2), 106 (armor level 1) and 169 (unarmored).

At 2.0m distance it's 509 m/s, damage 38 (armor level 2), 96 (armor level 1) and 153 (unarmored).

 

It looks a bit odd that the much smaller and lighter shrapnels of the russian gun seem to cause much more damage in a larger area and penetrate heavier armor than the german ones.

Other than that, the number at least seem reasonable to some degree, in comparison to each other (which by no means should be mistaken as an estimation of their correctness in absolute numbers).

 

Mike

[-SF-Disarray]

So a charge this small is doing damage to anything within about a 1 to 3 foot radius? That seems a bit much. It explains a bit of the effectiveness of HE rounds from HMG's though. Is there any indication as to how X damage translates to observed effect? I mean, knowing that a round dose 200 some odd points of damage is fine I guess but that doesn't mean very much.

[Honza]

@SAS_Storebror What are numbers for cannons in damage for comparison if i can ask? So we could see the difference between little hmg he filler compared to significantly bigger one in cannon rounds. 

[ACG_Cass]

Doesn't seem right. That's much closer to what you'd expect from a 20mm. 

 

The table from this paper (http://www.quarryhs.co.uk/WW2guneffect.htm) has some interesting maths behind. Of course they are pretty assumptive but they point out that the these figures line up with the German expectations that it took 4/5 times as many 20mm shells to destroy a heavy bomber, and roughly with the expectations that the US had for the number of 50 cals were vs a 20mm cannon. 

 

 

"To illustrate how this works: a typical cannon shell consists of 10% HE or incendiary material by weight. Multiplying this by ten gives a chemical contribution of 100%, adding the kinetic contribution of 100% gives a total of 200%. In other words, an HE/I shell of a given weight that contains 10% chemicals will generate twice the destructiveness of a plain steel shot of the same weight and velocity. If the shell is a high-capacity one with 20% chemical content, it will be three times as destructive. If it only has 5% content, the sum will be 150%, so it will be 50% more destructive, and so on.

The following table for the most common cartridges and loadings used in aircraft guns shows the consequences of these assumptions and calculations. The first few columns should be self-explanatory, as these are basic statistics about the ammunition. HE(M) means Minengeschoss, or high-capacity mine shell. The 'DAMAGE' column shows the results of the calculations described above. To run through an example, let us look at the case of the 7.7x56R (.303") incendiary. The projectile (a "De Wilde") weighs 9.8 g, (which equals 0.0098 kg) and was fired at 747 m/s. Multiplying these gives 747 x 0.0098 = 7.3206, so you have a momentum factor of 7.32. As the bullet contains 5% by weight of incendiary material, the momentum is multiplied by 1.5 to give a destructive power score of 10.98 - rounded to 11.

The last column - 'POWER' - takes into account that different types of ammunition, with different destructiveness scores, were commonly loaded into an ammunition belt or magazine. Many cannon shells were also available with tracers, which reduced the weight of HEI mix. This column therefore shows an average score for the different types to give an overall destructiveness assessment for that calibre. For convenience, the result is divided by ten and rounded to the nearest whole number (except for HMGs), which helpfully leaves the least powerful cartridges, the rifle calibre rounds, scoring 1."

 

 

 

 

[357th_KW]

A nice resource for the actual specifics of the various shells:  https://ww2data.blogspot.com/2017/05/german-projectiles-792mm-to-30mm.html

 

The 13mm projectiles had 18 grains of filler, either HE or HE with some thermite.

 

20mm MG151 HE projecticles had ~50-60 grains, and the mine shells had 260 grains.

[SAS_Storebror]

Thanks @KW_1979 however that resource is talking about guns and ammo used by ground troops, not aircraft guns/ammo.

God knows whether they all used the same type of ammo.

18 grains would be 1.17 grams...

Let's compare that with http://michaelhiske.de/Wehrmacht/Luft/Luft/LDV_4000/TEIL_03/Kap_01a.htm

The "13-mm-Sprenggranate L'spur" specs say "Die Sprengladung besteht aus 10% phlegmatisierter Nitro-penta und hat ein Gewicht von 1,17 g".

Fits.

Overview for 13mm is here: http://michaelhiske.de/Wehrmacht/Luft/Luft/LDV_4000/TEIL_03/Anlagen/ANLG_02.HTM

 

Mike

[Cpt_Siddy]

1g of explosive filler is laughably little. 

 

When i was kid, i used to play around with old soviet shell propellant charge pellets. We made all sorts of wacky stuff, but as long as the explosives were not in confined space, you needed 10g+ to even make a noticeable dent in old car hoods. In here, one hit form MG HE on most tail sections makes it weeble wooble like crazy. 

 

And by contained space, i mean something like 50cal shell casing, with its mouth cramped shut and thrown in to fire 

(I am lucky to be alive, i know, 90's were crazy fun times to be a kid, no interent and loads of old soviet hardware to play with)

[BCI-Nazgul]

6 hours ago, Cpt_Siddy said:

1g of explosive filler is laughably little. 

 

When i was kid, i used to play around with old soviet shell propellant charge pellets. We made all sorts of wacky stuff, but as long as the explosives were not in confined space, you needed 10g+ to even make a noticeable dent in old car hoods. In here, one hit form MG HE on most tail sections makes it weeble wooble like crazy. 

 

And by contained space, i mean something like 50cal shell casing, with its mouth cramped shut and thrown in to fire 

(I am lucky to be alive, i know, 90's were crazy fun times to be a kid, no interent and loads of old soviet hardware to play with)

Having some similar experience as a young chemistry major I completely concur with your opinion.  1 gram of explosive (even high explosive) is a laughably small amount to cause much damage to something like an airplane.  You are far better off trying to light the fuel.  Even the charge in a 20mm shell is not that really that big.  My father had a friend growing up that had a 1/4 stick off dynamite go off in his hand.  That's more HE than a 20mm can hold.  He lost 3 fingers and survived.  I've read accounts off crew members surviving 20mm HE hits in the extremities, their limbs were severed but they lived.  I believe the effects of HE are over modeled in this game by a large margin for the 20mm and under rounds.

Edited October 4, 2020 by BCI-Nazgul

[ACG_Cass]

 

Struggling to find a source on this one but that's pretty clearly a 30mm going into a Spitfire wing. From this and the hours of gun camera footage we can safely say that 30mm was devastating, but it's effect is very much concentrated in a specific area. The cockpit doesn't appear to be affected at all and it's a shit fairly close to the wing root.

 

 

In ther current iteration this would probably be engine damage, a wounded pilot and you'd have damage decals all over the plane. This is closer to what we see for 20mm and even then, they have a massive area of effect also.

[BCI-Nazgul]

9 minutes ago, Cass said:

 

Struggling to find a source on this one but that's pretty clearly a 30mm going into a Spitfire wing. From this and the hours of gun camera footage we can safely say that 30mm was devastating, but it's effect is very much concentrated in a specific area. The cockpit doesn't appear to be affected at all and it's a shit fairly close to the wing root.

 

 

In ther current iteration this would probably be engine damage, a wounded pilot and you'd have damage decals all over the plane. This is closer to what we see for 20mm and even then, they have a massive area of effect also.

Shells above 20mm do carry serious amounts of HE.  There is a relationship between the shell wall thickness required to survive firing and the amount of HE the shell can hold.  The proportion of casing to HE goes down in larger shells allowing them to hold much more HE compared to smaller shells.

[Cpt_Siddy]

People tend to forget that while diameter increase is linear, the volume increase is cubic. 

 

20mm shell had ~20 grams of TNT equivalent, while 30mm had nearly ~90 grams worth of oomph. The German 108 30mm cannon is what you would call today a grande machine gun. 

And yes, the 30mm hit is and should be lethal, and in game it does its job (unlike russian and murrican 37mms, that get eaten by 109 arse to this day).

 

The 20mm guns in this game are somewhat hit or miss, but the HMG explosive filled rounds are down right joke. If i had a option, where i could switch the 109's nose hub cannon for extra HMG, i would, its rate of fire and ammo pool paired with its aerodynamic damage on planes far outperforms anything else available for 109, even the 30mm.

 

Or maybe a quick fix by replacing current US 50 cal belt, say, with Russian one, i am sure no one find this objectionable, because there is nothing wrong with HE filler 50 cals, right? 

Edited October 6, 2020 by Cpt_Siddy

[SAS_Storebror]

Just throwing in another random find about entrance/exit damage caused by incendiary rounds, this one's an MK108 one but you get the ghist.

Entry hole:

 

Exit damage:

 

That's a Type L/M 3 cm Brenngranate ohne Zerleger (3 cm Brgr. o. Zerl.), filled with thermite, no HE filling.

Gives an idea of what the damage of non-he rounds looks like on exit side.

 

Mike

[ACG_Cass]

Zero questions about the lethality of 30mm, my point is around the area of affect for all HE weapons seems to be way overblown. 30mm should be devastating, but devastating to a fairly small area. 90g is still half what you see in a M67 hand grenade and what we are seeing in game, appears to be even more than that. A single 30mm hit to your wing will trigger the damage decals on your fuselage and the other wing. This certainly shouldn't be the case and it obviously affects all HE weapons as they are balanced against each other in terms of damage and area of effect. It's probably why we are seeing HE MG shells with 2g's of explosives in them causing such massive damage.

 

@SAS_Storebror funnily enough, that looks like exactly the same test plane! (I imagine they probably couldn't use it after the 30mm hit)

 

Potentially this is a limitation of the current iteration of the DM and in order for 30mm to have the correct affect, it needs to damage more of the plane. If that's the case I've no issue with it being left as it is. My main concern is that implementation being used on all HE rounds making 20mm and HE MG overly effective, and in tern leaving an AP round in the dust.

 

[alpino]

15 hours ago, SAS_Storebror said:

Just throwing in another random find about entrance/exit damage caused by incendiary rounds, this one's an MK108 one but you get the ghist.

Entry hole:

 

Exit damage:

 

That's a Type L/M 3 cm Brenngranate ohne Zerleger (3 cm Brgr. o. Zerl.), filled with thermite, no HE filling.

Gives an idea of what the damage of non-he rounds looks like on exit side.

 

Mike

I've posted those pictures of a plane shot by 50s and there were people saying it was definetly hit by modern explosive rounds.

[ACG_Cass]

https://history.army.mil/html/books/010/10-9/CMH_Pub_10-9.pdf

 

Page 422 onwards is very interesting. 

 

Also a telling quote...

 

 

 

 

[BCI-Nazgul]

2 hours ago, Cass said:

https://history.army.mil/html/books/010/10-9/CMH_Pub_10-9.pdf

 

Page 422 onwards is very interesting. 

 

Also a telling quote...

 

 

 

 

This sounds much closer to reality than the current situation.  However, I still think .50 AP is seriously underperforming in multi-player no matter what additional damage the API would do.  I have personal knowledge of German planes surviving and winning fights after being hit by 90+ rounds of .50 AP in multiplayer.   I also think .50 HE is grossly over-modeled.

Edited October 6, 2020 by BCI-Nazgul

[unreasonable]

Just a further thought on the HMG data:  a Browning Hi-Power fires a 9mm bullet of 7.5-8.0g, depending on type, at a MV of 350-400 m/s, depending on the type.

These are very similar figures to the German 13mm splinters in the data table: mass 7.1g, initial V 342m/s (assuming everything is SI).

 

So the 2 splinters from a 13mm "HE" shell should each do the roughly same damage as one pistol shot at the equivalent range. Unless the velocity of the closing impact before the explosion is also added to the initial velocity of each splinter - which it arguably should be but may not be, for simplicity.

 

The Soviet splinters are 3g at 535 initial V.   Closest I can find after a quick look would be a 22 LR round: 2.6g and a MV of 390: that is about half the KE of the Soviet splinter. So the soviet splinter is somewhere between a 22 round and a 5.56 NATO which is much higher velocity. 

 

 

 

 

 

 

 

 

 

 

Edited October 6, 2020 by unreasonable

[the_emperor]

9 hours ago, Cass said:

https://history.army.mil/html/books/010/10-9/CMH_Pub_10-9.pdf

 

Page 422 onwards is very interesting. 

 

Also a telling quote...

 

 

 

 

 

The M23 Round (more so the M1 Incendiary round) seems to bee close in composition and function to the German 13mm incedniary round.

That would also explain why the Luftwaffe dropped the HE and HE-I 13mm round since the pure incendiary is a dedicated air to air round to set unarmoured  (wing) tanks on fire.  This also makes more sense when encountering heavy 4-engine bombers, where small explosive will have no effect but the incediary round can set the tanks on fire with a high probability.

 

Edited October 6, 2020 by the_emperor

[ACG_Cass]

Big question is though: which one are they going to model? Because they all seem to have fairly different properties. 

 

M1 - great against fighters from the most aspects but, thanks to limited AP potential, lacked effectiveness on frontal attacks due to armour

M8 - good all rounder but when manufactured in meaningful quantities lost most of it's AP potential - not used 

M20 - tracer round that emerged in Spring 1944, apparently better than M1 or M10 - likely in a mixed belt with M1 + M10(tracer)

M23 - nuclear option designed for jet fuel and will light a damp cardboard box on fire - probably not going to be implemented

 

 

 

[Honza]

1 hour ago, Cass said:

Big question is though: which one are they going to model? Because they all seem to have fairly different properties. 

 

M1 - great against fighters from the most aspects but, thanks to limited AP potential, lacked effectiveness on frontal attacks due to armour

M8 - good all rounder but when manufactured in meaningful quantities lost most of it's AP potential - not used 

M20 - tracer round that emerged in Spring 1944, apparently better than M1 or M10 - likely in a mixed belt with M1 + M10(tracer)

M23 - nuclear option designed for jet fuel and will light a damp cardboard box on fire - probably not going to be implemented

 

 

 

M23 should be as BoBp represents end of war where this ammo was used and M20 should be around D-Day, i wouldnt mind both options. 

[the_emperor]

1 hour ago, Cass said:

Big question is though: which one are they going to model? Because they all seem to have fairly different properties. 

 

M1 - great against fighters from the most aspects but, thanks to limited AP potential, lacked effectiveness on frontal attacks due to armour

M8 - good all rounder but when manufactured in meaningful quantities lost most of it's AP potential - not used 

M20 - tracer round that emerged in Spring 1944, apparently better than M1 or M10 - likely in a mixed belt with M1 + M10(tracer)

M23 - nuclear option designed for jet fuel and will light a damp cardboard box on fire - probably not going to be implemented

 

 

 

 

Since US -Fighter where often tasked with strafing ground targets the M8 API and M20 API-T  would be the best all around option, as they are proven to be still highly effective (even though not as "nuclear" against air targets as the M23 round).

Those are also the rounds I would like to see in the russian 12.7mm, since (from my limit knowledge) the Blast effect of the 12.7 seems a bit small, especially when deployed against bigger targets like bomber with bigger control surfaces....

 

On the other hand for the 13mm MG131 I would like to see the HE and HE-I gone und replaced with the Incendiary Round which should work like the M23 round described above as an dedicated Air to Air round (notably if you have to have face heavy 4 Viermots, wich carried large fuel tank, which could be set on fire with that kind of round and the HE Blast damage would bem neglectable since they only do minor surface damage and dont penetrate deep).

Edited October 6, 2020 by the_emperor

[FTC_Zero]

I See the German 13mm discussed a lot here. How does it perform in-game? 

[messsucher]

15 minutes ago, ZeroCrack01 said:

I See the German 13mm discussed a lot here. How does it perform in-game? 

 

The same as .50 cal, while being of a higher caliber? Just guessing.

[-SF-Disarray]

38 minutes ago, ZeroCrack01 said:

I See the German 13mm discussed a lot here. How does it perform in-game? 

 

In game I'd say the 13mm HE round performs more like I'd expect 20mm HE rounds. 2-3, though in some cases 1, hits is all it takes to cripple or kill a fighter in most cases. Speed losses from a small number of 13mm HE hits can be as high as 30-50 KPH, controllability after these hits is typically nonexistent to absolutely combat ineffective. Against bombers the 13mm HE rounds aren't as catastrophic though it usually doesn't take more than 5-10 to bring down an A-20 if you hit them properly, and if you have particularly good angles and aim you can do it in less. In short, this is an absurd level of overperformance for a round containing such a small amount of HE filler.

 

I can't speak to the effect of 13mm AP rounds as it seems none of the 13mm MG's in the game shoot them due to an apparent bug. Though if the 12.7mm Breda guns on the 202, which due to a similar bug seem to fire nothing but AP, and the way the US M2's AP rounds behave I'd expect the 13mm AP rounds to be as ineffective as these other AP rounds.

[ACG_Cass]

@ZeroCrack01

 

There are certainly some issues...

 

Although not as apparent as on the P-51, you do see similar effects on control surfaces on other allied planes when they have taken minimal hits.

 

After some testing, 50s will take off the control surface before they affect the roll rate.

 

 

[-SF-Disarray]

What's interesting is I've seen the exact opposite behavior at least once in a 190-D9. Lose function in one aileron and the plane still rolls like it always did.

 

https://www.twitch.tv/videos/754676154

 

This could be a one off kind of fluke but I suspect that it isn't given how often I've seen planes raked with AP rounds to no apparent effect.

Edited October 6, 2020 by -SF-Disarray

[Cpt_Siddy]

I dont remember what plane it was, but if you lost one vertical stab, you can actually pull harder G's 

 

Was either soviet or axis, 109 maybe? 

Edited October 6, 2020 by Cpt_Siddy

[FTC_Zero]

5 hours ago, -SF-Disarray said:

 

In game I'd say the 13mm HE round performs more like I'd expect 20mm HE rounds. 2-3, though in some cases 1, hits is all it takes to cripple or kill a fighter in most cases. Speed losses from a small number of 13mm HE hits can be as high as 30-50 KPH, controllability after these hits is typically nonexistent to absolutely combat ineffective. Against bombers the 13mm HE rounds aren't as catastrophic though it usually doesn't take more than 5-10 to bring down an A-20 if you hit them properly, and if you have particularly good angles and aim you can do it in less. In short, this is an absurd level of overperformance for a round containing such a small amount of HE filler.

 

I can't speak to the effect of 13mm AP rounds as it seems none of the 13mm MG's in the game shoot them due to an apparent bug. Though if the 12.7mm Breda guns on the 202, which due to a similar bug seem to fire nothing but AP, and the way the US M2's AP rounds behave I'd expect the 13mm AP rounds to be as ineffective as these other AP rounds.

Sorry, but this is just ridiculously delusional. Michael Bay would be proud of you. Yes, I am the one asking here, but even I have enough trigger time with 13mm and 20mm to tell the difference. 

[-SF-Disarray]

1 hour ago, ZeroCrack01 said:

Sorry, but this is just ridiculously delusional. Michael Bay would be proud of you. Yes, I am the one asking here, but even I have enough trigger time with 13mm and 20mm to tell the difference. 

 

I never said that the 13mm HE rounds are behaving the same as the 20mm HE rounds in game. I said, very clearly, that the 13mm HE rounds, in game, are behaving like I'd expect 20mm HE rounds to behave. Not the 20mm HE rounds in game, but based on written accounts and photographic evidence of 20mm HE impacts in real life examples. And even that might be underselling it a little given the frequency that a single impact from a 13mm HE round can kill a plane. You can think I'm wrong if you like. But go and investigate it yourself. If you are feeling particularly ambitious go get yourself some video from in game showing just how wrong I am. I'll wait, and if I'm 'ridiculously delusional' I shouldn't have to wait too long.

[Cpt_Siddy]

If i had a choice to put the German heavy machine guns everywhere, like have 190 with 6 HMG's that we currently have in game, i would, They have higher rate of fire, better ballistics and loads of ammo. Even few hits from them usually render any plane unable to run or be a stable gun platform and they set planes on fire at higher than average rate. 

 

20mms have higher per round damage, sure, but they have worse ballistics, worse rate of fire and less ammo. And having 2 or 3 HMG hits from the german 50 cal HE ammo does the same thing or more than single 20mm. 

 

If i could have P-38 loaded with German HE MG ammo, i would have become death, destroyer of the worlds. 

[Honza]

3 hours ago, Cpt_Siddy said:

If i had a choice to put the German heavy machine guns everywhere, like have 190 with 6 HMG's that we currently have in game, i would, They have higher rate of fire, better ballistics and loads of ammo. Even few hits from them usually render any plane unable to run or be a stable gun platform and they set planes on fire at higher than average rate. 

 

20mms have higher per round damage, sure, but they have worse ballistics, worse rate of fire and less ammo. And having 2 or 3 HMG hits from the german 50 cal HE ammo does the same thing or more than single 20mm. 

 

If i could have P-38 loaded with German HE MG ammo, i would have become death, destroyer of the worlds. 

I think 13mms were designed with same or extremely close ballistics to mg151/20 so it would be easier to aim. Not 30mm tho, it have around 200m/s lower muzzle velocity and massive drop. 

[FTC_Zero]

5 hours ago, -SF-Disarray said:

 

I never said that the 13mm HE rounds are behaving the same as the 20mm HE rounds in game. I said, very clearly, that the 13mm HE rounds, in game, are behaving like I'd expect 20mm HE rounds to behave. Not the 20mm HE rounds in game, but based on written accounts and photographic evidence of 20mm HE impacts in real life examples. And even that might be underselling it a little given the frequency that a single impact from a 13mm HE round can kill a plane. You can think I'm wrong if you like. But go and investigate it yourself. If you are feeling particularly ambitious go get yourself some video from in game showing just how wrong I am. I'll wait, and if I'm 'ridiculously delusional' I shouldn't have to wait too long.

If 13mm HE behave like you would expect 20mm HE to behave then what do 20mm HE/Minengranate 'in-game' mean to you right now?

[-SF-Disarray]

HE damage across the board seems to be overblown. 20mm rounds will shred entire wings, 30mm rounds will hit one wing and damage the entire plane including the wing on the other side of the plane. Generally speaking, the damage should be toned down a bit and much more localized to the point of detonation.

[TheSublimeGoose]

I’ve been saying this for a couple of years now (mainly on the IL-2 Reddit); but the US .50s are, IMO, not modeled accurately, and still aren’t, even (if not especially) post-DM update.

 

I speak from two sources; historical & personal.

 

Historically, pilots speak of 6-8 .50s absolutely decimating anything they touched. Pilots speak of sawing wings/tails off, seeing blood explode on the inside of cockpits, etc, all from a couple of bursts. Look at combat footage from the time. One, maybe two bursts from the .50s and that airframe is at least out of action. Obviously A LOT comes down to good convergence, I’ll readily admit that. But a well-converged 8-gun burst of .50s — do people understand how much lead that is impacting a (relatively) small area?

 

A one-second burst from 8 .50s put out 4.44kg (9.8lbs) of lead. A single MG 151/20 put out 1.38kg/s. This put the 47’s armament in league with x3 151/20s, in terms of burst-mass alone. Now, does it seem that way in-game? Don’t get me wrong; I fully understand that burst-mass isn’t everything, and it certainly doesn’t take into account explosive content (or lack thereof). But it counts for something, which is why it’s a heavily-used metric in any formula that attempts to calculate weapon ‘power.’

 

Then, personal experience; I’ve seen what a single HMG does to engine blocks, vehicles, people, concrete, even steel. And these weren’t special rounds, for the most part they were simple ball rounds. I can’t imagine what a converged 8 would do.

 

In-game, I can chase around 109s, putting burst after burst into them, and the keep on putting along. Yes, occasionally I’ll get a pilot kill. But that’s a rarity. More often than not it’s a long game. Merely from turning the aircraft surface into Swiss-cheese, it should be unflyable. Pieces should instantly fly off when hit with a well-converged blast. But don't take my word for it....

 

I realize this is mostly anecdotal, but what I've noticed is that some folks get really defensive about this. Are we just going to ignore the video posted on the first page? 205 rounds to kill a K-4, lol.

Then we get to the point that no one is denying, and yet some folks act like it's not a big deal; U.S. late war belts absolutely should have API and API-T rounds. Not pure AP with occasional AP-T. According to Flying Guns World War 2: Development of Aircraft Guns, Ammunition and Installations 1933-45, early-war .50 belts should be  "...loaded with 40% [M2] AP, 40% [M1] incendiary and 20% [M1] tracer..." while late-war belts were "...loaded with the M8 API..." with the occasional M20 API-T for tracers. Some pilots opted not to load tracers, as "...the tracer fell out of favour when it was realised that it was providing more help to the enemy." Interestingly, the M23 incendiary (carrying a whopping 5.83gr of incendiary composition) saw some late-war use, as well. Accordingly, IMO, we should have two belt options for the 51 and 47; A 'standard' belt with M8 API and the occasional M20 API-T, or a 'stealth' belt of pure M8 API. I truly believe this would go a long way in terms of effectiveness of the current AN/M2s.

 

As for the Breda 12.7mm, it didn’t even have half the explosive content of the MG 131 13.2mm round (0.8 grams PETN for the Breda, 1.4 grams PETN & 0.3 grams thermite for the 131). The Breda also had a lower RoF than most .50s, which became abysmal when synchronized to a prop (as in the 202) coming in at 575/min.

 

If anything, I think x2 Breda-SAFAT 12.7mm outperforms x8 well-converged M2s in many cases, which is simply BS. Perhaps they’d be better at igniting a fuel fire, but that’s about it.

Oh, then there's the Soviet UBS round... if I recall it carried quite a lot of explosive filler?

[messsucher]

1 hour ago, -SF-Disarray said:

HE damage across the board seems to be overblown. 20mm rounds will shred entire wings, 30mm rounds will hit one wing and damage the entire plane including the wing on the other side of the plane. Generally speaking, the damage should be toned down a bit and much more localized to the point of detonation.

 

I tend to feel this way, coming from original IL-2, but can't really say which is more realistic, no idea which.

[messsucher]

59 minutes ago, KotwicaGoose said:

A one-second burst from 8 .50s put out 4.44kg (9.8lbs) of lead. A single MG 151/20 put out 1.38kg/s. This put the 47’s armament in league with x3 151/20s

 

Are you sure you have done the math right? Since this certainly surprises me.

[HR_Zunzun]

14 minutes ago, messsucher said:

 

Are you sure you have done the math right? Since this certainly surprises me.

43gr per rounds times 13 rounds per second times 8 guns in the jug is 4472gr per second (4.4kg)