Disadvantages
With the increased safety of the black powder substitutes often comes a reduced sensitivity to ignition. Flintlocks in particular need very sensitive, finely granulated powder for use in the flash pan, and black powder tends to perform more reliably in these and traditional caplock guns than substitutes. Modern in-line muzzleloaders provide a stronger ignition than traditional designs, and this helps to increase reliability with the less flame sensitive substitutes. In addition, magnum percussion caps are often recommended for use with black powder substitutes for both inline and traditional caplock guns, in place of the #11 percussion caps traditionally used with black powder in these guns, to achieve the best ignition reliability.
When used for recovery system ejection charges in high-power rocketry, black powder substitutes need a greater degree of confinement to ensure a complete burn and generation of sufficient ejection pressure. This can be achieved by wrapping 2–3 layers of electrical tape over the ejection charge canister before installation.
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