there's like maybe two weapon packs that do that.
sweps (ok this pack does use cool extra mag removing debris thingy but that it still counts)
t+t all versions
h+k
blockality
frog's weaponary
star wars laser weapons
pretty much most of old rtbs weapon mods
and lastly blockombat or whatever it was called
for me it doesn't add character but instead show how lazy the creator is
I mean making a "default", "blocky" styled mod with brick animations ain't that hard
not that I hate the packs I've listed above but I like when there is more animation than slightly moving your hand a few times