The .40 round is very sensitive to set-back and I am convinced that an early Glock 22 I was issued instantly achieved entropy because of it.
There is no magic distance that I am aware of at which one round becomes dangerous.
Shoot up your ammo every year and get fresh rounds. Even if you have to buy them out of your kids' college fund, it is cheap insurance.
Dear God, this is one of the dumbest ideas I've ever heard. It's got to rank right up there with CALEA. -Pepper45
Bastard! - TBO