This sounds like a bad solution to a real problem. You can talk to some folks here in No. VA about strays getting away from the DC Police range.
A little math applied to the problem says that a ricochet from the concrete pipes, and there will be some, can go well over 100 ft. high at the end of the range. Is the hill at that end at least this high? And what will they say when folks are picking concrete and lead fragments out of their face when someone hits the near end of the pipe?