Gamo Rocker Pellet Trap Resets with center shot

my first impression when i took it out of the box was i thought the outside metal case was to thin for my pellet gun but after 20 shots, the trap is still stopping the pellets. it is starting to dent a few places from repeated shots in the same place but the pellets haven't gone through yet. i have a feeling the pellets are going to punch a hole through one of these days. i'm going to have to become a better shot because the five targets show no signs of damage when a pellet strikes it. i have a hatsan striker .177 spring pellet gun