Yes, they are composites, no black powder. However, as you can image, Robert does not release his formula. I can only say it is a white, very strong, but also flexible propellant that is pressed at the manufacturing process. His machine (I saw photos, but cannot publish them) produce them automatically, and works very accurate (measures the powder weight for each engine to ensure a high quality) according to Robert.

Since his formula has a higher degree of efficiency than the black powder Weco used, he will be able to produce D-size 18 mm engines for example. His F will have about 60 g´s of propellant and fits into the 29 mm casing.

The only bad thing is I guess they won´t be available before the end of this year or even later.

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