olauzon said:dear berlowmj,
what are you? mississippi? hudson? colorado? either one, be sure you use hi crome rebar and pH basic concrete. shoot all shitting birdsthat may surround you with salt pellets and hopefully that way they will likely spill elsewhere.
jokes aside. the length depends on the width. when i shoot wide i use a shorter bridge and when i'm dead on i increase the distance. if i shoot low i step back and the vise versa for follows.
hope this helps.