109 vs Spitfire

[Charge]

"I'd love to see proof of that."

As Karnak said at typical engagement ranges the difference was negligible.

As a further confirmation that MG151 had the more desirable concept is the excellent Hisso V which was a more compact weapon and better than MG151 in some respects, e.g. if we leave out the better "chemical effect range" of MG151 which was never pursued by the Hisso team during the war, even if the examples of German MG ammo were available. But then again the Brits never needed to shoot down heavy bombers so they were not in acute need of it.

If you think about the lead shooting and think how much less lead angle you would need if the muzzle velocity was slightly higher and consider the trade off in ammunition weight and gun weight to get that, there is certainly a sweet spot where these matters, including aircraft speeds and theoretical accuracy i.e. ability to instictively shoot at correct lead, cross. I'd say MG151 and MK108 were pretty near the sweet spot, as is evident by the immediate post war development of DEFA and ADEN cannons where compactness, caliber and ROF were considered more important than MV. As the speeds increased further in jet age the MV came important again, but that is another story.

Does that sound like proof?

-C+

[Butcher]

If the Hispano was a far better gun, any reason the german's didn't steal it from the french or british early in the war? After all they had to develope the mg151 fron scratch.

[Karnak]

If the Hispano was a far better gun, any reason the german's didn't steal it from the french or british early in the war? After all they had to develope the mg151 fron scratch.

It wasn't a far better gun.  That is what Charge and I are both saying.  We'd take MG151/20s over the Hispano in real life.

The Hispano has a higher muzzle velocity and superior AP performance.  In all other ways it is inferior.  The MG151/20 has a higher rate of fire, better shells, smaller shells for more ammo in a given space, was more reliable and it weighs less.

[Butcher]

It wasn't a far better gun.  That is what Charge and I are both saying.  We'd take MG151/20s over the Hispano in real life.

The Hispano has a higher muzzle velocity and superior AP performance.  In all other ways it is inferior.  The MG151/20 has a higher rate of fire, better shells, smaller shells for more ammo in a given space, was more reliable and it weighs less.

Ahhh ok sorry, I got lost twice in the article and simply couldn't figure out what was being argued lol I found it a bit surprising... I was trying to read a bit on german munitions and see if they ever took hispanos for testing, its always interesting to read jsut why they used MG151s or MK108s for example.

After seeing the Mk103, I only dream of having 109K4 with it.

[titanic3]

Ahhh ok sorry, I got lost twice in the article and simply couldn't figure out what was being argued lol I found it a bit surprising... I was trying to read a bit on german munitions and see if they ever took hispanos for testing, its always interesting to read jsut why they used MG151s or MK108s for example.

After seeing the Mk103, I only dream of having 109K4 with it.

The Mk103 was too large for the 109 iirc.

[Babalonian]

Fight!! 
Aircrafts cars and bikes arent sexy. Girls are.   

Honestly, I've driven a couple of each of them around a block.  In the end, only one of those doesn't get you any resale/turn-in vale when you're done and tired with it. 

[Karnak]

Well, one other place the Hispano seems to have been superior is in the standard HE round.  The MG151/20's Minengeschoß is significantly superior to the HE rounds of either gun, but Minengeschoß rounds were not used exclusively.

[Noir]

If the MG151/20 was that much better in real life, why isn't it the same in AH? Should it make more damage per shell than the hispano?

[Charge]

No, or it depends. MG151/20 has ample performance to penetrate aircraft armor on practical engagement ranges but on long range Hisso is still better. MG151 has better chemical energy on long range and thus retains better overall energy also on extreme ranges after the KE of Hisso starts to wear out, but as the damage model does not differentiate between HE and AP the overall power of Hisso is better on all ranges, which is generally correct with a simplified damage system.

Why is it simplified then? E.g. IRL AP performance is not as straightforward as it is not just about punching holes in armor and structure but more of how much of KE can be released into structure. E.g at close range an AP round may penetrate and leave a nice clean hole in surface and supporting structure and pass though the plane into blue beyond, but on longer range the AP round in similar place may tumble, change direction and tear structures much worse as it now releases all its energy upon target and do much worse damage than that fired from close range.

-C+

[Wmaker]

Tony Williams on this board about the rate of fire of the Hispano Mk.II:

The official RoF for the Hisso II was 600 rpm and this seems to have been the actual average. Of course, as with any automatic gun this could vary a lot depending on the circumstances. I have read that even straight from the factory, the RoF could be anything between 550 and 650 rpm due to production tolerances. The quality of the maintenance the guns received also made a difference.

Considering the fact that most things on AH are modelled on the basic specs that are given by the manufacturer the rate of fire in AH should be 600rpm instead of 650rpm.

I just clocked free firing MG151/20 in game. It has a rof of 700rpm. Tony Williams' site lists 720rpm: http://www.quarry.nildram.co.uk/WW2guneffect.htm

[Karnak]

If the MG151/20 was that much better in real life, why isn't it the same in AH? Should it make more damage per shell than the hispano?

Other than the Minengeschoß rounds the Hispano's were better.  If you had a belt of Minengeschoß then yes, but AH models an average damage and the poorer performance of the MG151/20s basic HE round hinders it.  I seem to recall that in the common belting only one in five or six rounds was a Minengeschoß.

[Noir]

Other than the Minengeschoß rounds the Hispano's were better.  If you had a belt of Minengeschoß then yes, but AH models an average damage and the poorer performance of the MG151/20s basic HE round hinders it.  I seem to recall that in the common belting only one in five or six rounds was a Minengeschoß.

Got me confused there, I thougt the Minengeschoß was the ammo for the MG/FF. I'm gessing Minengeschoß is an ammo type, derived for different guns.

In any case we have another perked ordinance possibility here 

[Charge]

MG was available for both 20mm and 30mm guns.

MG-FF was initially only capable of firing AP and standard HE. MG-FF/M was able to fire also MG ammo as it required a minor change in the gun.

According to Schiessfibel June 1944 the standard beltings were: 3 MG - 1 Incendiary - 1 API for general use, against bombers it was: 1 MG - 1 incendiary - 1 API, and of course a wide variety of different mixes what ever the pilot fancied.

I recall that 4 MG - 1 API was also a common composition as well as MG - HE - HE - AP, but I don't recall the source.

-C+

[Karnak]

Minengeschoß is a "shell round" that has a much thinner metal shell and much higher HE content.  As Charge notes it was available for the MG151/20 and MK108.  Not sure about the MK103.

It is already factored into the MF151/20's average damage in AH.  Instead of three rounds hitting for 3lbs of damage and one round for 5lbs of damage you get four rounds hitting for 3.5lbs of damage in AH.

[GScholz]

In the Luftwaffe ammo belt composition was the prerogative of the pilot so it could be anything really. However the recommended standard early-mid war was 2x HE(M), 2x AP(I) and 1x HE(T), so two out of five would be minengeschoss. 1944/45 the AP(I) rounds were often dropped in favor of more HE(M) or HE(I) (aka Brandgranatpatrone 44, a minengeschoss round filled with an incendiary/explosive mix and a special fuze that detonated when in contact with liquids), especially in anti-bomber units.