Why always trying to ruin this game with this type of comment, try to give positive suggestions to improve the game.
Nothing to "remove" or "reduce".
you want positive?
lets INCREASE the density of the zed's bodies, so they stop MORE pellets.
how about... some pellets go through, some pellets don't.
it could start as something like... 25% chance of 1 penetration, and a 10% chance of a second penetration (per pellet) at lvl 1 (nothing or perhaps 10% for 1 penetration, null for two at lvl 0)
and increasing each lvl, to eventually something like 75% of first penetration, 25% of second penetration (again, per pellet, not shot)
so, for example, a shot fires 10 pellets.
of those.... 6 stop at the fist zed 4 go though the it. of those remaining 4, 3 stop at the second zed, and a single pellet reaches a 3rd (and last) zed.