Military ammo can uses go far beyond storing ammunition — these are some of the most versatile pieces of surplus kit you can buy. Built to survive the harshest battlefield conditions, these heavy-duty metal boxes turn out to be extraordinarily useful once you get them home. If you’ve picked one up and aren’t quite sure what to do with it beyond stacking it in the garage, you’re in for a pleasant surprise.
In this guide, we run through 10 genuinely brilliant military ammo can uses, from practical storage solutions to creative DIY projects. Whether you’ve bought a classic British Army .30-cal box or a large .50-cal can, there’s something here for everyone.
What Makes Military Ammo Cans So Useful?
Before diving into specific uses, it’s worth understanding why ammo cans are so well-suited to repurposing. Genuine military-spec ammo boxes are constructed from heavy-gauge steel with a rubber or neoprene gasket seal around the lid. This gives them three properties that most commercial storage boxes simply can’t match:
- Waterproof and airtight — the gasket seal keeps moisture, dust, and insects out entirely
- Virtually indestructible — the steel construction can take serious knocks, drops, and abuse
- Lockable — most ammo cans have a hasp that accepts a standard padlock
Add in the fact that they’re stackable, relatively lightweight for their size, and available for a few pounds on the surplus market, and it’s easy to see why people find so many uses for them.
1. Emergency Survival Kit Storage
One of the most popular military ammo can uses is building a bug-out or emergency survival kit. The waterproof seal makes an ammo can ideal for storing the essentials you’d want to grab in a hurry: a fire-starting kit, emergency rations, a first-aid kit, a torch, spare batteries, a mylar blanket, and a copy of important documents. A .50-cal can has enough room to store a solid 72-hour kit for one person.
Because the box is airtight, your matches, tinder, and paper documents stay bone dry no matter where you store it — whether that’s in the car boot, a garden shed, or a damp loft space.
2. Camping and Bushcraft Gear Organiser
Campers and bushcrafters love ammo cans. A mid-sized box is perfect for organising fire-lighting gear — fire steel, tinder, kindling, lighters, and a small folding knife — and keeping it all together in one grab-and-go container. The rigid steel construction means you don’t have to worry about items being crushed in a rucksack or truck bed.
Many overlanders use multiple ammo cans mounted to their vehicle’s roof rack or rear carrier, each dedicated to a specific category of gear: one for cooking tools, one for recovery kit, one for first aid.
3. Secure Document and Valuables Storage
A military ammo can with a padlock through the hasp makes for a surprisingly capable safe. While it won’t stop a determined thief with power tools, it’s an excellent deterrent against opportunistic theft and a solid way to protect documents, cash, passports, or small valuables at home or in a vehicle. The airtight seal also means your contents are protected from water damage in the event of a flood or a burst pipe.
4. Outdoor First Aid Box
If you’re involved in outdoor activities — hiking, mountain biking, climbing, four-by-four off-roading — having a proper first aid kit is essential. An ammo can is one of the best containers for a vehicle-mounted first aid kit. It’s robust enough to rattle around in a truck without damage, it keeps your supplies dry, and it’s immediately recognisable if you paint it with a red cross. Inside, you can store wound dressings, tourniquets, bandages, antiseptic wipes, and medications without worrying about packaging getting crushed or wet.
5. Faraday Cage for Electronics
This is a use that’s become increasingly popular among preppers and survivalists. A sealed metal container acts as a basic Faraday cage — a shield against electromagnetic pulses (EMP) and solar flares that could fry unprotected electronics. By lining the inside of an ammo can with a non-conductive material (such as cardboard or foam) and placing your spare electronics inside — a backup radio, a spare phone, a battery bank — you create a low-cost EMP-resistant storage solution.
It won’t offer the same protection as a purpose-built Faraday cage, but for the price of a surplus ammo box, it’s a remarkably cost-effective safeguard.
6. Tool Storage in the Workshop or Garden
Workshop clutter is a perennial problem, and ammo cans are a stylish, practical solution. Because they stack neatly and seal tightly, they’re brilliant for storing small hand tools, drill bits, screws, nuts and bolts, spark plugs, or any other small items that tend to go wandering. Label each box on the outside and you’ve got an organised, moisture-resistant storage system that will last a lifetime.
In the garden, ammo cans are ideal for storing seeds, plant labels, and small trowels — particularly useful if you have an allotment or outdoor potting area where kit regularly gets left out in the rain.
7. Fishing Tackle Box
Anglers have long appreciated the waterproof properties of ammo cans. A small .30-cal box is the ideal size for carrying lures, hooks, weights, line, and a multi-tool for a day’s fishing. The seal keeps saltwater out if you’re sea fishing, and the metal construction means you don’t have to worry about dropping the box on a slippery riverbank.
Some keen anglers even drill a small hole in the side and fit a handle to make their ammo can tackle box even more convenient to carry.
8. Geocaching Container
The geocaching community has embraced ammo cans enthusiastically. A military ammo can makes a perfect cache — it’s weatherproof, spacious enough to hold a logbook and small tradeable items, and robust enough to be buried, hidden under rocks, or tucked in dense undergrowth without deteriorating. The metal construction means animals can’t chew through it, and the rubber seal keeps the interior dry for years on end.
If you’re placing a cache, a .30-cal ammo can is typically large enough to be classed as a “regular” cache, which is one of the most popular sizes among geocachers.
9. Off-Grid Power Station Case
With a bit of DIY skill, an ammo can can be converted into a portable power station for camping or off-grid use. The conversion typically involves cutting holes in the lid for USB ports, voltage displays, and switches, then mounting a 12V battery, charge controller, and solar panel connection points inside. The result is a weatherproof, portable power box for charging devices in the field.
There are plenty of step-by-step guides online for this conversion, and the ammo can’s dimensions make it a natural fit for a 12V lead-acid or LiFePO4 battery.
10. Pet Food and Bird Seed Storage
Finally, one of the most straightforward military ammo can uses: storing dry pet food or bird seed. The airtight seal keeps contents fresh and — crucially — keeps rodents out. If you’ve ever come down in the morning to find a mouse has chewed through a bag of guinea pig pellets, you’ll understand the appeal. An ammo can is a permanent, pest-proof solution that will outlast every plastic container you’ve ever bought.
Which Size Ammo Can Should You Buy?
Military ammo cans come in several sizes, and the right choice depends on what you plan to use it for:
- .30-cal (small) — ideal for first aid kits, small tool storage, tackle boxes, geocache containers
- .50-cal (medium) — the most versatile size; perfect for survival kits, camping gear, document storage
- 40mm or large format — best for tools, pet food, off-grid power builds, or larger cache collections
Genuine British Army surplus ammo cans are among the most robust available, having been manufactured to exacting military standards. They’re also widely available and very affordable.
Shop Military Ammo Cans at Surplus Cases
Ready to put one (or several) of these ideas into action? Browse our full range of military ammo boxes and surplus storage cans at Surplus Cases. We stock genuine British Army surplus ammo boxes in a range of sizes, all at competitive prices with fast UK delivery. Stock levels on genuine surplus items change regularly, so don’t wait too long if you spot something you need.
Whether you’re building an emergency kit, organising your workshop, or heading off on a camping expedition, a military ammo can is one of the best-value purchases you’ll ever make from the surplus world.
