This high-speed film is from Virgil Tripp's site. Not WWII weapons, but it shows what happens when small arms are fired.

JT

Tripp Research, INC. Hi-Speed Video

It would have been better with a a machine gun.

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Looking at the shot exiting the barrels, it is interesting to note the amount of flame visible, which means (to me anyway) that the powder is burning outside of the weapon itself, thus no longer imparting any force on the projectile.

Does this mean that the cartridge has more than the necessary amount of propellant or is that the combustion of the powder is inefficient? or both?

Would one way to improve the velocity of a weapon's projective be to develop powder that fully combusted within the weapon? Right now with what is being used, it looks like to accomplish this, you would need a barrel considerably longer than would be practical.

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Best Regards,
JW

A guess

The flame you see is comparable to the steam of a steam whistle. What you see has already done it's job.

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