I just realized you can use health to create bullets and quickly parry to regain that health...

I've played through many times, all chalice dungeons, platinum trophy. Whenever I run out of bullets, I desperately use some health to get +5 and then quickly chug a blood vial to cover my back.

I only just realized I can always have free +4 if I use one for a parry kill right away. Those guys outside cathedral ward are perfect for some free bullets.

What other tricks am I missing??