Same principle - putting egg in a plastic jar of peanut butter works too. Provided the plastic jar is lightly padded. It takes a lot less padding to project the

Same principle - putting egg in a plastic jar of peanut butter works too. Provided the plastic jar is lightly padded. It takes a lot less padding to project the plastic jar than a naked egg and the viscosity of the peanut butter means that the egg won't drift from the center of jar.