been told 4.7 grains is what I should be aiming for
Hopefully you have checked multiple sources before deciding on a starting load. The 9mm can be very sensitive to changes in bullet seating depth. And all bullets are not the same length, so DO NOT assume the same OAL will give the same pressure when changing bullets of the same type and weight.
Bullseye is a fast burn rate powder and you are more likely to get into problems with it than a slower burning powder.
Keep asking questions, and enjoy your new hobby.