my bow is set at 68 pounds my current arrow is 27 and 1/8 inch's long

if i go to a 400 grain arrow at 271/8 long will that be to heavy for my weight

also if i re sight my 20 yard pin for the 400s is there any way i can set my 30 ad 40 close before shooting so when i shoot at 30 and 40 i am not shooting into the woods or something