Use Mortar Racks to Make Your July 4th Fireworks 100x More Exciting!

Blue and gold fireworks

Although the Chinese are making bigger and better assortments of festival balls (also called “shells,” “artillery shells,” or “reloadables”), they are still being stingy with mortar tubes for them.

If you only have one or two mortar tubes, you end up with a lot of shells to reload, which is just plain slow and boring to you and the audience.

Now if you’re like most folks, instead of firing one shell every minute or two, you’d rather blast 10, 20 or 30 shells into the air all at one time! Now THAT’S what we wanna see, RIGHT?!!

But before I show you how to make that happen, this is a good time to get something cleared up, so you and I are speaking the same language.

The TUBE is the mortar, not the little thingy you drop down in them that goes boom in the sky. That thingy is called a SHELL, which is fired out of a mortar.

Mortar equals tube

Mortar does not equal shell

Shell equals aerial fireworks

Shell does not equal “mortar”

Mortar tubes are also called “guns” by old fireworks pro’s. But a fireworks pros would never get caught calling a shell a “mortar,” no matter how many people call ‘em that.

Got it?

Now you’re ready to start blasting fireworks up in the air like the pro’s do it.

So how DO you get more shells into the air, either at the same time, or faster than you can hand fire them. Well, the first thing you need is…

More Mortar Tubes.

Let’s say you want to launch 25 shells at same time or one after the other in quick succession. Well obviously you’re going to need a lot more mortars.

So let’s look at your tube options first.

Mortar Tubes 101

Fireworks mortars are usually made from 3 different materials: cardboard, high density polyethylene (HDPE), and fiberglass. These are the safest tubes to use for fireworks mortars. The reason is that an explosion in such mortars will cause the tube to rupture, tear, or shred, but they will not break into flying pieces of sharp shrapnel. For that reason you should never use PVC or metal pipes to make fireworks mortars. You would not believe how and sharp PVC can be when it is exploding at you at 500 miles an hour!

Cardboard Mortar Tubes: Cardboard tubes are the least expensive mortars. carries cardboard fireworks mortars. They’re cheap, but you have to do a little work. You need to either plug one end of them with wood, or make wooden bases for them. Easy enough to do if you’re handy with tools. And to make cardboard tubes last longer than one use, you should soak or coat them in polyurethane or varnish. This makes the cardboard waterproof, and keeps them from unraveling due to moisture. Cardboard mortar tubes are your cheapest option

Fiberglass Mortar Tubes: Fiberglass tubes are typically made in China with a concrete plug in the bottom. So that part is done for you. They are the middle priced alternative: they cost more than cardboard, but are less expensive than HDPE. The good new is that with reasonable care, they should last a lifetime. You should wear gloves to keep from getting fiberglass splinters in your hands. Fiberglass mortar tubes are in the mid-level of price.

HDPE (high density polyethylene plastic) Tubes: This is typically black plastic pipe, but sometimes comes in other colors. HDPE need to have wooden plugs screwed and glued into the bottom. Although their cost fluctuates with oil prices, they are usually the most expensive mortars. But they can last a lifetime, and are very safe to use.

But which tube you get depends more on the size of your shells as anything.

Aerial Shells 101

Shell Size: Consumer fireworks shells come in a variety of dimensions and shapes.

Consumer fireworks shells also called festival balls, artillery shells or reloadables
Consumer fireworks shells. Also called “festival balls,”
“artillery shells,” or “reloadables.”

So, if you’re shopping for mortar tubes, you need to know which mortar tube to look for. And to do that, you need to first measure the outer diameter (OD) of your reloadable shells. Measure the “widest” part, where the fuse goes around the shell. Write that dimension down.

There is no standard-sized Chinese festival ball shell. Unfortunately, there is no single size. They vary from around 1.67 to 1.88 inches in diameter, sometimes a little more.

As obvious as it may sound, how do you know when a shell fits in a mortar?

The right answer is that your shells should drop freely into the mortar. As long as the shell moves freely in the mortar, then the tube with the least amount of clearance should fire the shell the highest. Too little clearance, and the shell won’t even go into the mortar. And conversely, a mortar with too much clearance won’t launch as high and can cause your shell to explode lower in the sky, scattering burning stuff on the ground or your head.

Do Your Shells Fit Your Mortars?

So, make sure you get shells that fit your mortars, and that your extra mortars the right size for your shells

Now sometimes shells just seem to be too tight to fit the mortar. Try this: if they are a little snug, you can often roll the fuse side of the artillery shell against something smooth like a counter top, pressing down on the artillery shell hard as you do it. Try and roll the fuse a little flatter. Then see if you can drop the shell into your mortar tubes.

When you load your mortar tubes, be sure the shells go all the way down to the bottom. If a shell is not sitting on bottom when it fires, you will either get a low break–possibly injuring someone or starting a fire–or you could even get a “flowerpot.” A flowerpot occurs when the shell doesn’t lift out of the mortar tube, and explodes inside it. Both conditions can be dangerous. So make sure, when you load your mortar, that all shells are firmly seated on the bottom of their tubes.

Mortar Racks 101

If you want to fire more than one shell either at the same time, or in sequence, you will need a mortar rack to hold multiple tubes. Here are some options.

Option #1 – Make a cardboard mortar tube rack. Cardboard tubes don’t come with plugs in them. And forget using plastic bases for shells this large-most plastic bases blow apart the first time you use them. And no, cardboard caps and plugs aren’t made for this. If you want to reuse your mortar tube rack more than once, first dip/roll your cardboard mortar tubes in an oil-based varnish and let dry for a day. (I hang mine on coat hangers from a tree.) This seals them up, and keeps moisture from causing them to unravel.While they are drying, get yourself an adjustable hole-cutter/drill-bit like this one (Home Depot).

adjustable hole cutter

Then get a piece of 2 x 4 or 2 x 6 about as long as you want. Cut/drill round holes in the 2 x 4 about 1/2 inch deep just wide enough to hold one mortar tube. They can be holes or grooves. Either will work. Your mortar tube should fit into the hole snugly. Cut as many holes as you want. Use white/carpenter’s/Elmer’s glue (NOT hot melt, which will... well, get hot and… melt). Glue your mortar tubes down into the holes. Let them dry for a day. Et voila! You have a cardboard mortar tube rack like this one:

cardboard mortar tube racks

Option #2 – Make or buy a ready-made mortar tube rack. They look like this.

fiberglass mortar tube rack

You can find plans for making one of these at fiberglass mortar tube racks here.


The Secret to Buying Mortar Tubes and Not Starting Marriage Quakes

Of course, if you build these racks, you will need a lot of mortar tubes. When I first started getting serious about my July 4th displays, I just disciplined myself and made and bought more racks every year. I found out the hard way that if I waited to May or June, those mortar tubes were either hard to find, and/or they got more expensive the closer to July 4th I got.

Eventually I smartened up. I started buying mortars during the off months, when the pyro suppliers were holding sales on them.


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