Muzzleflashes unrealistic?

Originally Posted by swiss

Contact with air?
How do you wanna do that - create an anaerobe climate inside the cartridge? If so, where do take the oxygen needed for the combustion from?

There is a reason gunpowder has the shape of lil' balls(or cylinders): More space for O2 in between.

Please correct me if I'm wrong.

..or u can put a cover in front of the tracer phosphorous component, which will burn when the powder goes off

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