BC337 performance is marginal in this situation. ZTX851 would be better, with a 4K7 base drive resistor (any lower and you will exceed the 70mA total current rating of the 74HC595).
BC337 performance is marginal in this situation. ZTX851 would be better, with a 4K7 base drive resistor (any lower and you will exceed the 70mA total current rating of the 74HC595).