hispano vrs. Mg151

[Urchin]

I think he meant in AH, Mandoble.  

I'd agree with him, by the way, but it is clearly explained by the way the ammunition is modelled.  

At least relatively clearly... my first post in the thread details how it is modelled, to the best of my knowledge.

[Wotan]

Its simple.

Here's my hypothesis:

In AH impact velocity is more important then chemical energy.

The Hispano 'hits harder' (retains velocity at greater range) then the mg151 or mgff. Because mg151 and mgff have a lower mv and lose energy faster their potential damage falls off with range. Test the mgff at sat 200 yards then at 250 then at 300 for example.

Chemical energy makes up a smaller portion of the damage 'value' (correct word...?).

Il2 is having similair issues, so has wbs.

[MANDO]

AH? Well, IMO, in general, the main problem is the structural damage of AP rounds. Here, a P51 can cut a Lancaster wing with a single long burst, or even cut the lancaster in half. With the example of P51 50s (AP only), just imagine what hipanos can do.

[Wotan]

What you have is a lot of high velocity HMG rounds hitting the wings accumulating damage. After so many hit the wing falls off. They are no wing spars or cables to be cut through etc...

Its the same reason why you fly at high speed and get hit by the bomber defensive guns and very few hits kill you.

You high speed + the velocity of the 50s coming at you = greater impact velocity ir greater damge.

We tested this somewhat for the first BoB event. We had our ju88s slow down so that the attackers closure rate was as fast as possible when they dove from high 6. This increased the effectiveness of the ju88s guns and as such the ju88s had more kills and a higher k/d the any other aircraft.

Of course the ju88s were being shot at by 303s and you wont get the same results in a b24 when attcked by 3cm.

[HoHun]

Hi Charge,

>What is the distance in your calculations HoHun? Do your calculations show the values at 0 yds ie. the power with the initial muzzle velocity?

Roger that. However, if you figure in speed loss while the projectile is going downrange, the balance hardly changes.

Assumptions: Hispano rounds down to 500 m/s velocity, German rounds (1:1:3 mine shell belting) down to 300 m/s (subsonic!). That's pretty far down the range, and though I have no idea on whether the two points coincede, I consider these assumptions pessimistic for the German cannon.

MG 151/20 (MX): 1,16 MW (300 m/s)
MG 151/20: 0,97 MW (300 m/s)
Hispano V: 0,89 MW (500 m/s)
Hispano II: 0,74 MW (500 m/s)
MG-FF: 0,64 MW (300 m/s)

The results have not changed much - while the German shells have retained less speed than the Hispano projectiles, kinetic energy is only the smaller contributor to total energy, so it doesn't matter much.

The MG 151/20 with standard mine shells at subsonic speed is still within 10% of the Hispano II at full muzzle velocity.

Regards,

Henning (HoHun)

[TimRas]

Table from Luftwaffe Shooting guide, the  Schiessfibel

Sprenggranate= HE shell
Brandgranate= Incendiary shell
Panzersprenggranate= Armor-Piercing Explosive shell
Panzerbrandgranate= Armor-Piercing Incendiary shell
Panzergranate= Armor-Piercing shell

Durchschlagsleistung= Penetration power
Sprengwirkung = Explosive effect
Brandwirkung= Incendiary effect

Keine =None
Gering= Small
Mittelmassig= Average
Gut = Good
Sehr Gut = Excellent





MG151/20 belting for missions against heavy bombers:
1 Mine+ 1 Incendiary+1 API

Against other planes:
3 Mines+1 Incendiary+ 1 API

[HoHun]

Hi Timras,

>MG151/20 belting for missions against heavy bombers:
>1 Mine+ 1 Incendiary+1 API

>Against other planes:
>3 Mines+1 Incendiary+ 1 API

Thanks a lot, that sort of confirms my assumptions about belting!

Page 14 also re-inforces I point I've made in some other threads: Dispersion doesn't help you. The Schießfibel:

"Accordingly [referring to example illustrations for faulty deflection shooting], don't rely on weapon dispersion - it won't help you if your aim is flawed! You can see here clearly how ACCURATELY you have to know and to apply deflection, or your fire will miss. But if you think now that you could simply adjust your MGs for a larger pattern to hit more reliably, then you're making a mistake. Your experience will be similar to that of the wild hunter in the picture on the right."

The latter advice is repeated on page 28:

"Another thing: Please don't invent new harmonization patterns, for example by adjusting the trajectory cross-over 100 m out etc. The ordered harmonization has been carefully devised by combat veterans and is good."

Regards,

Henning (HoHun)