I have some old corregated black pipe, like you bury in your yard to run rainwater away from the gutter downspout. I cut it into pieces about the size of a decent silver carp, and toss the pieces off the deck, and shoot from on the deck. Works great. Reel them in, pull them off, and throw them back out again. Comes off easy, and you can put a lot of holes in one before it gets too shot up to be useful. Good for teaching kids before you take them out in the boat. Tougher to keep their attention on the various safety aspects when you are on the water, and you can get the motions established before excitement and fish enter the picture. And being able to reel in the "catch" provides a success aspect that is nice.