Dynamite Harry has you killing people with explosions. The best place to do this is on King of Chinatown. Start the missions, go through the doors and down the stairs. Pass by the stalls and then take a left. You should see a small alley and a fancy car. There's also a guard in this area, likely just behind the boxes on the right looking left.
Wait for him to walk up the stairs and have a phone conversation. Follow him up the stairs and stand right behind him. You should find the Remote Explosives just to your right. Take him out if you like or just take the explosives. Try to find a good crowd of guards and blow them up.
This is also easier if you play the last chapter, Absolution. Play the Burnwood Family Tomb (the second area). Take the first left and then go just inside the little area to the left. Distract the guard to the right with a brick and then keep going left from cover to cover until you find mines and explosives. Just toss them into the enemies nearby for a lot of damage.
