Well thats where i beg to differ!I doubt you can mod a stock bolt to be as good as a firebolt...tbh.
As the front of the stock is differnt and the metal and stuff like that. But i suppose for £6 it MAY be worth it...
The Firebolt makes the Ion/SP8 and i quote:
"faster,lighter and quieter while dropping the operating pressure about 15 psi."
Thats what my mod does,the only difference is the colour,mine weighs in at 24grams,compared to the Firebolts 16.8grams
Don't take my word for it though,ask IonGale,proof is in the pudding as people say!!