Fill large bowl halfway with ice and water. Set aside.
Bring 3 cups water to boil in large saucepan over high heat. Stir in shrimp and 1 tablespoon salt. Cover and turn off the heat until the shrimp are opaque, about 5 minutes, shaking saucepan every few minutes.
Transfer shrimp to ice bath and let cool for 3 to 5 minutes. Once cool, cut each shrimp crosswise into about 1/2 pieces. (larger shrimp 3 pieces, smaller shrimp in half.)
Combine V8 juice, ketchup, lime juice, hot sauce, and salt in mixing bowl. Add cucumber, onion, and shrimp and stir until evenly coated. Gently fold in avocado and cilantro.
Serve with lime wedges, chips and extra hot sauce on the side.