You will need:
20 pounds of Ammonium Nitrate Fertalizer
20 ounces of Motor Oil
Mortar and Pestle
Bucket and Disposable mixing stick/spoon
4x 2" by 6" Steel Pipes
8x 2" Steel Pipe Caps
Blasting Cap
Gas Mask (Wear at all times just in case)
Gloves (Wear at all times)
Drill
Funnel
Glass bottles (Or large chunks of misc metal) (Shrapnel is optional but reccomended)

Step 1: Break the bottles outside and make sure to safely collect all the glass and set it aside for later, if you're using the chunks of metal or not using shrapnel, skip this step

Step 2: Use the mortar and pestle to crush the Ammonium pellets into a fine powder, (the fertilizer MUST be at least 32% nitrogen otherwise the bomb wont preform as well as it can. (The powder will go bad if left out in open air for too long, move on to the next step as soon as the powder is ready.

Step 4: Mix the Oil and Powder at a 1:16 ratio in the bucket (1 being oil, 16 being powder) make enough to fill to about 3/4 of the six inch pipe

Step 5: Carefully funnel the mixture (and your choice of shrapnel) into the pipe (make sure the end you're pouring it in has a cap at the bottom) after that, make sure to drill the other cap to thread the blasting cap fuse through the hole (make sure the hole is airtight so the gas expands and creates a maximum force shockwave).

Step 5: Repeat until all ingredients are spent, tighten all caps or seal them with silicone

Notes:
-Never breathe in the fumes or dust made as a product of the crushed fertilizer
-Do not tamp the mixture into the pipe
-Recipe makes 4 pipe bombs
-Can be used with arduino to trigger blasting cap remotely
-If you're using shrapnel, you might want to use less mixture to fit the shrapnel more snug
-Make sure the fuse is long or short enough to your liking, it must be long enough for you to get away, but short enough so that they don't