I see what you are getting at

I thought you wanted me to shoot through the trash can not into it.
So the round will expand when it hits the water.I did not know that.
I will have to look around for a 55 gal steel drum.
Will a plastic trash can(55gal) work. That's all I have.or will it blow up?
I thought that a bullet will ricochet off water?
How far should the muzzel be from the cushion?.
Mike