I can tell you how to do it but I wont hold your hand.
1 You need to know how to bulletspam first.
2. You need to extract the calculation for bullets from the client which would have the exact calculations required.
3. You need to build a script or bot to send your bulletspam and then do the calculations for each bullet individually.
bonus: If you are smart you could figure out how to save yourself a lot of calculation time for bullets but thats up to you.