The short answer is that gunpowder weapons in general, and firearms in particular, evolved over a long period of time in Europe. There were certainly powers that had more experience with gunpowder weapons and the tactical usage of firearms, and those with less, but all had some familiarity with them due to the centuries of use that preceded wide adoption.

If you narrow your question to a more specific part of the technology (gunpowder itself, hand firearms, artillery, matchlocks, etc.) I can elaborate - some of them did have short periods of "surprise", even if that was more often due to innovative usage than the technology itself being unknown.