i don't go really deep into the holes at all with the slurp gun. it'll usually pull anything that's in a burrow out within two pumps. i just put it in the mud, and apply a little downward pressure on the tube while lifting on the plunger, then yank it out and dump the contents on the beach before the suction breaks. you're not trying to pull the mud out of the hole like a clam gun, just water and shrimp. it really works best close to the waterline or where there's a little standing water.

not sure i'd want to use anything else on the hoquiam tide flats, that stuff is heavy and stinks to high heaven. i can usually get a couple dozen shrimp within 20 minutes or so with the slurp gun.