What Is a Beer Mortar? How It Works and How to Use It Safely

What is a beer mortar? It is a cannon-shaped bottle opener that sits on top of a metal bottle cap and, with one palm strike, pops the cap off and launches it upward. Half opener, half party trick, it runs on a spring and a piston rather than batteries. This guide explains how a beer mortar works, how to use one step by step, which bottles it fits and the safety rules that keep the trick fun. If you want to see the real thing first, here is the Beer Mortar.

What is a beer mortar, exactly?

A beer mortar is a mechanical bottle opener shaped like a small cannon, or mortar, the short artillery piece that fires upward at a steep angle. The name describes the motion: you place it on the cap, aim at the ceiling or the sky, strike once, and the cap leaves the bottle going up instead of dropping onto the table.

Three things set it apart from a regular opener:

• No leverage from you. A classic opener needs you to hook the cap and pull. A beer mortar is pushed straight down onto the cap, so the work comes from one downward strike.
• No electronics. There is no battery, no app and nothing to charge. A spring and a piston do the job.
• The cap flies. That is the whole point. Opening the bottle becomes something the table watches.

Beer mortars sit in the "novelty opener" family alongside wall-mounted openers, cap catchers and keychain openers. Our novelty bottle openers comparison explains what each type is good at, including when a launcher is the wrong choice.

How does a beer mortar work?

Photo: Ccyyrree / Wikimedia Commons (CC0)

A beer mortar works by turning one downward palm strike into an upward push on the edge of the cap. To see why that opens a bottle, start with the cap itself.

A standard beer cap is a crown cork, invented by William Painter in Baltimore and patented in 1892. It is a thin metal disc with a liner and a ring of crimped "flutes" that lock under the head of the bottle (Wikipedia: Crown cork). Any opener, from a bar key to a lighter, does the same job: it bends those flutes outward until they no longer grip the glass. Our article on the history of bottle caps covers why that 19th-century design is still on almost every bottle.

The Beer Mortar does it in one motion:

1. The mortar rests flat on the cap. Its base sits over the crown, so the mechanism is lined up with the crimp.
2. Your palm strikes the top. The strike drives the spring-loaded piston inside the body.
3. The crimp lets go all at once. The mechanism lifts the cap's edge off the glass lip. The cap is released in one go and travels upward, out of the mortar's muzzle.

The energy comes from your hand, not from the carbonation in the bottle. If you want the numbers behind the flight (why the cap spins, how high it goes and why it never lands in quite the same place), read the physics of a bottle cap trick shot.

How to use a beer mortar, step by step

Using a beer mortar takes about three seconds once you have done it twice. Before the first try, read the quick-start card that comes in the box.

1. Pick the spot. Choose a clear area with open space above: a patio, a garage, or a room without hanging lights directly overhead. Look up before you launch.
2. Stand the bottle on a stable surface. A flat table or bar top, not a lap or a wobbly folding chair. Hold the bottle steady with your free hand if you need to.
3. Rest the mortar flat and centered on the cap. It should sit square, not tilted. A tilted mortar sends the cap off at an angle.
4. Aim upward. Point the mortar at the ceiling or the sky, never across the table.
5. Check the flight path. Nobody leaning over the bottle, no pets nearby, nothing breakable above.
6. Give the top one firm, straight palm strike. Straight down, through the center. The bottle opens and the cap flies.
7. Pick up the cap. Crown caps have sharp edges and are easy to step on or for a dog to find.

A few tips for a clean launch

• A cold, unshaken bottle foams less. A bottle that has been rattling around in a bag or sitting warm is more likely to foam over after opening. Our guide on how to chill beer fast helps with the first part.
• Strike, don't push. A slow press tends to bend the cap without launching it. One quick, firm strike works better than several soft ones.
• If the cap stays on, lift the mortar, re-seat it flat and centered, and strike again. Do not use a hammer or any tool on the mortar.
• Skip damaged bottles. If the neck or lip is chipped or cracked, open that one with a regular opener, or not at all.

Then pour as usual. Our guide on how to pour a beer covers glass angle and foam.

Which bottles work with a beer mortar?

Photo: KMJ / Wikimedia Commons (CC BY-SA 3.0)

A beer mortar is made for standard metal crown caps, the pry-off kind with a crimped edge. That covers most glass beer bottles, from lager and IPA to stout, plus hard seltzers and craft sodas sold in capped glass bottles.

It is not meant for:

• Cans. There is no cap to launch.
• Plastic screw caps. They need twisting, not lifting.
• Swing-top (flip-top) bottles. The wire clasp opens by hand.
• Corked bottles. Champagne, sparkling wine and some Belgian-style beers use corks, which need their own handling.

A quick check: if the top of the bottle looks like the cap in the photo above, with a ring of small pleats around the edge, it is a crown cap.

Beer mortar safety rules

A launched cap is light, but its edge is sharp, and eyes do not tolerate small impacts. Follow these rules every time:

• Launch upward, into open space. Never toward a person, a face, a pet, a TV, a mirror or a window.
• Check the ceiling. Pendant lights, glass shades, ceiling fans and smoke detectors sit right in the flight path indoors.
• Nobody directly above the bottle. Friends tend to lean in to watch. Ask them to step back.
• Keep it away from children. A beer mortar is an adult's bar tool. Store it out of reach, and supervise closely if children are around when it is used on a soda bottle.
• Pick up every cap. A cap on the floor is a hazard for bare feet and for curious dogs.
• Not after a few too many. Aim and judgment matter, and the trick is no fun for anyone if someone gets hit.

Drinking age and drinking responsibly

Beer is for adults of legal drinking age: 21 in the US under the National Minimum Drinking Age Act, and 18 to buy alcohol in the UK (GOV.UK). A beer mortar opens a capped craft soda or an alcohol-free beer just as well, so everyone at the table can have a turn. The fun is in the opening, not in how many bottles get opened. NIAAA's Rethinking Drinking site has practical tips on pacing an evening.

Beer mortar vs a regular bottle opener

A regular opener is still the right tool for a quiet night or a crowded room with a low ceiling. If you are caught without either, see how to open a beer without a bottle opener. For a small everyday companion, the CapBlast lever opener fits on a keyring.

The bottom line

A beer mortar is a mechanical, cannon-shaped bottle opener that opens a crown-capped bottle and launches the cap upward in one palm strike. Using it well comes down to three habits: rest it flat and centered, strike straight down, and always aim at open space with nobody above the bottle. You can see how the Beer Mortar works on its product page, or browse more ideas on our gifts for beer lovers page.