I don't know much about silencers but I'm guessing the spring you are talking about is to absorb the shock. So if a .22 isn't powerful enough to move the spring then it probably doesn't have enough power to hurt the can either.
I have mostly non-sporting firearms
In NJ, technically speaking, ALL guns are illegal
Also in my state there is such thing as a Class III BB gun :barf:
Happy to say that despite the NJ AWB I still manage to make my guns look scary