Do you guys thik a Crosman 664 gt could kill a female turkey (hen) .

It may at very close range , BUT it is not ethical.
A pellet gun like that dosn't have enough penatration to cleanly kill a turkey.
Is turkey season in ?
I bet even if it is in ,a air rifle is not legal to hunt turkey with.
Why chance a ticket at your age .
What would you do with it after you shoot it ?
What would your parents say about you POACHING ?

whats with all these stupid crap I hear about is it ok to shoot deer with a 22 and turkey with a bb gun c'mon use some common freakin sense here crap im not to fond about squirrel hunt with a bb gun

Killin a squirrel with a bb gun? Its a pellet gun, they have more than enough power if you have the right one.