WW2 aviation ammo

[pbehn]

so true, i guess we will never know. as everything got bigger and stronger faster and heavier we end up with an A10

If the RAF had the 0.5" that was fitted in 1944 available in 1940 things may have been different, but it is a what if, the USA was also using rifle calibre guns early in the war for the same basic reasons.

 

[tomo pauk]

i was pointing out that 6 browning .303 as produced for the RAF produced more energy of shot than 4 .5 brownings in a 1.5 second burst. given the difference is weight of both guns and ammo and rate of fire. i did not state that as you say a spitfire with 6 brownings. i was trying to clear up why the british stuck with the .303 round rather than change to the .50.

I can't be bothered to do the math, so Shortround6's answer is also my answer.
British stuck to .303 because the 20mm was too late.

Sinderd Fluke. think of it as a very hard steel dart inside a lead bullet.

Googling 'Sinderd Fluke' again returns blank.
If you have a picture of ww2 era .303 ammo that has a 'very hard steel dart inside a lead bullet', please share.

Hispano. some thing i would not have thought about if you had not pointed it out. nor have i ever read any thing about it. do you have a link to more information please

For the starters, look at this schematics. The 20mm and lower .50 on the P-38 differ in drop by only two inches between 150 and 450 yds (and presumably well after 450 yds). Bullet drop difference is a good indicator of external ballistics difference.

 

[pbehn]

I

Googling 'Sinderd Fluke' again returns blank.
.

I believe it is sintered fluke. "Sintered alloy fluked ammunition" returns some hits. Sintering is a process using heat, in steelmaking used to increase the efficiency of the furnace, no idea of how it works on munitions I suspect using metal powder and heat in some way. Flukes can be the barbs on an arrow or the tail fins of a whale as well as a lucky shot.

 

[Greyman]

No it doesn't

AIR FIGHTING DEVELOPMENT UNIT | TACTICAL AND ARMAMENT TRIALS - SPITFIRE VC
8 March 1942
SPITFIRE VC - 4 x 20 mm. CANNONS

Manoeuvrability

The Spitfire Vc with full war load was flown to a height of 30,000 feet. At this height the rate of climb was below 1,000 feet per minute and the aircraft became exceedingly sloppy. Although the rate of climb at 28,000 feet was approximately 1,000 feet per minute, the manoeuvrability was not good and it is thought that it could be easily out-manoeuvred by the Me.109F.

Dog-fights were carried out at heights from 10,000 to 20,000 feet between a Spitfire VC and a Spitfire VB with full war load, and it was found that in all respects the Spitfire VB was slightly more manoeuvrable. The manoeuvrability of the Spitfire VC above 20,000 feet rapidly falls off, and the advantages in favour of the Spitfire VB are even more marked. During the climb to 20,000 feet the rate of climb of the two aircraft was compared and it was found that the climb of the Spitfire VC was not quite so good as that of the Spitfire VB.

The Commander of the AFDU forwarded the report to HQ, Fighter Command with the recommendation:
Squadrons equipped with Spitfire VC fitted with 4 x 20 mm. cannons should not be operated above a height of 20,000 feet.

In April 1942 it was proposed to equip a single squadron in each of Nos. 10, 11 and 12 Groups with Spitfire VC aircraft armed with 4 x 20 mm. guns. "Operational experience with the all 20mm and mixed armament in the Spitfire is required to decide the most suitable armament for these aircraft."

On 1 June 1942 a conference was held at HQ, Fighter Command:

Future Employment of the Universal Wing for Spitfires and Typhoons and the Best Combination of Armament for Future Types of Fighters

The C-in-C (Air Marshal Sir Sholto Douglas) said the Conference was called to see if it was possible to decide the most suitable combination of armament for fighter aircraft and what standardisation was possible, and also whether the universal wing was still required. The universal had been designed at a time when we were short of 20 mm. guns and did not know if we had enough guns to go round. Production, however, had been able to keep us well supplied. Another reason for the use of the universal wing was that it allowed flexibility in choice of armament for certain types of operations and against different types of enemy aircraft. It was however 100 lbs. structurally heavier than the ordinary Spitfire wing. It was also more difficult to produce. It has unsightly bulges which detract from speed. If it is possible to agree upon the best armament for the Spitfire and the Typhoon universal wing can be got rid of.

The conclusions reached were almost unanimous. Groups 9, 11, 12, 13, and 82 did not want the universal wing and wanted an armament based around 2 x 20mm guns. 14 Group had no experience with the universal wing and 10 Group wanted the universal wing just in case future requirements revealed a need for 4 x 20mm.

Air Vice-Marshal Sorley added ... the Spitfire was being overloaded. The more the weight put on it the greater the loss of performance. ... We are now committed in production to the universal wing for the Merlin Spitfire.

In the wake of this conference, on 8 June 1942, Air Marshal Douglas wrote the Air Ministy:

The Armament of Spitfire and Typhoon Aircraft

I consider that the universal wing for all types of Spitfire aircraft now serves no useful purpose and that it means the addition of an appreciable amount of unnecessary weight to the Spitfire. In view of the need to improve the Spitfire performance, particularly in regard to climb, I propose that the universal wing should be dropped. Instead I recommend that armament of this aircraft should be standardised at 2 x 20 mm. and 4 x .5 guns, with ammunition for 15 secs. fire for all guns. If this requirement cannot be met, I am prepared to accept 2 x 20 mm. and 2 x .5 guns, with the same ammunition load as above. This recommendation applies also to the Spitfire XX (Griffon). ...

The decision to dispense with two of the 20 mm. guns in the Spitfire VC wing should enable this wing to be considerably cleaned up and some of the bulges removed, which are detrimental to performance. I should be grateful if immediate steps could be taken to this end, in particular on the Spitfire IX.

Ironically, the only times I ever saw gun heating mentioned as an issue with the universal wing was in regard to the outer Brownings.

 

[Greyman]

Found another bit:

Regarding the 4 x 20 mm. alternative armament for the Spitfire XIV ... the Ministry of Aircraft production state that it is not possible to give clearance for this armament at present on weight considerations.

- AVM J. D. Breakey, 12 January 1944​

 

[alsaad]

Don't you guys read?

https://archive.is/KAqG

 

[alsaad]

must read:

RAFHS 08