22 barrel length

I have a stock talon and and I love it right out of the box, but as air gunners know that is not good enough. I just got a 18″ barrel from Tony at TT with a shroud and they look great. Have not tried it yet but can’t wait. I also have a 24″ barrel coming from synopsys (great deal), my question is , what can I expect from the different lengths and do I need a heaver hammer or different top hat setting.