The closer to the muzzle the deflection occurs, the wider the miss.
I have my own tale of woe, involving a TC Hawken, a Maxi Ball, and a nice buck I thought was in the bag.
Idaho_Shooter has it right; any bullet can be deflected. Pass on those shots, unless the obstruction is very light, and very close to the target. Even then stuff can happen. Your little disaster is one that's hard to avoid because stuff up close is almost invisible through a scope. You were lucky to get a clean miss.
