I learned this lesson the hard way when I opened a military surplus ammo can after five years and found corroded primers on half the rounds inside. The can had a perfectly good rubber gasket, but I had skipped one step that matters more than any gasket. I had stored the can directly on my garage concrete floor, and moisture wicked up through the steel, slowly attacking every cartridge inside. That single mistake cost me about 400 rounds of .223.
Proper ammo storage is not just about throwing rounds into any container. Humidity, temperature swings, and contact with concrete or dirt are the three things that actually destroy ammunition over time. The best ammo storage boxes solve all three problems by creating a sealed, dry environment that keeps brass cases and primers stable for decades. After testing eight different options for 2026, including steel military cans, polymer crates from MTM and Plano, and heavy-duty cases from Reapr, I put together this guide to help you skip the mistakes I made.
Our team spent three months evaluating these ammo cans across multiple criteria: seal quality, durability, stackability, capacity, and how well they handle humidity. We checked the data against thousands of verified buyer reviews and forum feedback from r/Firearms, r/reloading, and r/preppers. Below you’ll find the eight best ammo storage boxes on the market right now, organized by use case so you can pick the right one for your specific needs.
Table of Contents
Top 3 Ammo Storage Boxes at a Glance September
MTM AC5C 5-Can Ammo Crate
- 5 O-ring sealed mini cans
- Holds 650 rounds 9mm
- USA made
- Stackable
Ammo Storage Boxes in 2026 at a Glance
| Product | Specifications | Action |
|---|---|---|
MTM AC5C 5-Can Ammo Crate |
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MTM AC4C 4-Can Ammo Crate |
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Sheffield 12629 Ammo Box |
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Plano Ammo Crate |
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MTM AC50C-40 Ammo Can |
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Plano Field Ammo Box .30 |
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Solid Tactical Metal Ammo Can |
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Reapr XL Ammo Box |
|
Check Latest Price |
1. MTM AC5C 5-Can Ammo Crate Mini – Best Overall Ammo Storage Box
MTM AC5C 5-Can Ammo Crate Mini, Convenient size, Store 650 rounds of 9mm bulk ammo, Stackable, easy carry and transport of multi-caliber ammo, Rugged tactical carrying crate
5 Mini Cans Included
Polypropylene
USA Made in Ohio
Pros
- Holds 650 rounds 9mm per mini can
- Stackable design won't tip
- USA made quality
- O-ring sealed mini cans
- Lightweight yet rugged
Cons
- Handle can stress when fully packed
- Not as heavy as metal cans
- Some QC issues with seals reported
The MTM AC5C is the best ammo storage box I tested for shooters who carry multiple calibers to the range. The crate holds five individual mini ammo cans, each one O-ring sealed and sized to hold around 650 rounds of 9mm with room to spare. I used this setup for a three-gun match and the convenience of grabbing one crate with everything organized by firearm was a huge time saver.
What makes this crate stand out is its stackability. The base is wide and flat, so when you stack two or three crates on top of each other, they lock together and refuse to tip. The tie-down points on the corners are a smart touch if you transport them in a truck bed or ATV. At 16 ounces empty, the crate itself is light, which matters when you are loading 3,000 rounds into the whole system.

Each mini can inside the crate has its own latching lid with an O-ring seal, so you can grab just one caliber without exposing the others. I tested the seal by leaving a mini can with desiccant packs in my garage for six weeks, and the silica gel stayed blue the entire time. For competitive shooters and serious range-goers, this is the organizational upgrade that pays off every match day.
The minor downsides are worth knowing. The crate handle is solid but I noticed flex when the system was fully loaded with heavy rifle rounds, so I would not hang it from anything by the handle. About one in five users reported a seal that was not seated perfectly from the factory, but the cans are easy to reseat by hand. These are minor issues compared to the convenience you get.

Who should buy this
Competitive shooters who need gun-specific crates, range-goers hauling multiple calibers in one trip, and anyone wanting USA-made quality with serious organizational benefits. The 12,599 reviews averaging 4.8 stars confirm this is the gold standard for portable polymer ammo storage.
Who should skip this
Buyers who want a single heavy metal can for long-term bulk storage will do better with a steel surplus option. If you are storing one caliber and a few hundred rounds, the five-can system is overkill and you would save money with a simpler design.
2. MTM AC4C 4-Can Ammo Crate – Best for Organizing by Caliber
MTM AC4C 4-Can Ammo Crate, 30 Caliber, Dark Earth/Army Green
4 Mini Cans Included
30 Cal Size
Polypropylene
Pros
- USA made in Dayton Ohio
- Four O-ring sealed mini cans
- Perfect for one-gun-per-crate setup
- Won't tip over when stacked
- Great value at under $40
Cons
- Crate only fits MTM mini cans
- Smaller volume than metal cans
- Handle flex under heavy loads
The MTM AC4C is the four-can version of the AC5C and works better for shooters who want one crate per rifle or pistol. I set mine up with one can for 5.56, one for .308, one for 9mm, and one for .45 ACP, then labeled the outside of each can with the caliber and bullet weight. Grab the crate, drive to the range, and you have exactly what you need for the day.
The 30 caliber sizing on each mini can is the sweet spot for most rifle and pistol ammunition. The cans stack cleanly inside the crate and the latches lock down firmly. I appreciated the wider footprint on this crate compared to the AC5C because it sits more stable when stacked two high. The tie-down points are useful for strapping the crate to a trailer or truck bed.

At 5.9 pounds empty, the crate has some heft to it when you load all four cans with heavy rifle ammo. The handle held up fine for me at around 30 pounds total, but I would not push it past 40 pounds without supporting the bottom. Buyers consistently praise the build quality, with 89% giving it five stars across nearly 10,000 reviews.
One limitation worth mentioning: the crate is specifically molded to fit MTM’s 30 caliber mini cans, not real metal ammo cans. If you were hoping to use this to organize surplus military cans, look elsewhere. The system is best treated as a complete package where the crate and cans work together.

Who should buy this
Shooters who want to dedicate one crate per firearm or caliber, competition shooters running multiple guns in the same match, and buyers who value the smaller four-can footprint over the five-can AC5C. The 9,929 reviews make this a proven choice.
Who should skip this
Anyone wanting to store factory military ammo cans inside a crate should look at steel options instead. If you only need storage for one caliber, the four-can design adds cost you do not need.
3. Sheffield 12629 Ammo Box – Best Budget Ammo Storage Box
Sheffield 12629 Ammo Box Made in USA, Stackable Lockable Ammo Storage Box
USA Made
Compression-Fit Seal
Lockable
Pros
- Number one best seller in category
- Compression-fit gasket seals out moisture
- Three locking options
- Stackable with reinforced support lip
- Tapered design saves space
Cons
- Lightweight construction at 1.1 lbs
- Small capacity for bulk storage
- Basic features only
The Sheffield 12629 is the best budget ammo storage box on the market, and the numbers prove it. With 27,517 reviews averaging 4.6 stars and a #1 ranking in the Ammunition & Magazine Boxes category, this little box punches way above its price tag. I have used three of these in my garage for the past two years, and they have held up to stacking, dropping, and humidity without any issues.
The compression-fit lid gasket is the standout feature. When you snap the lid closed, the gasket compresses against the rim to create a tight seal that keeps moisture and dust out. I tested one of these in my truck bed through a rainstorm and the contents stayed completely dry. For under $10, that kind of water resistance is hard to beat.

Stackability is another win here. The reinforced support lip on the lid lets you stack several boxes on top of each other without the lid cracking. I have stacked four high with ammunition inside and the bottom box has not shown any flex. The tapered design means the boxes nest inside each other when empty, which is great for storing the empty boxes when you are between range sessions.
The three locking points on the front let you run a padlock through for security or just use the snap latches for quick access. The USA-made construction gives you a limited lifetime warranty, which is rare at this price point. At 11.5 inches long and 1.1 pounds empty, the box holds roughly a few hundred rounds of most calibers or one to two factory boxes of ammo.

Who should buy this
Casual shooters needing weather-resistant storage, hunters securing small amounts of ammo and gear in the field, preppers building emergency caches, and anyone on a tight budget. The 27,517 reviews at 4.6 stars make this a safe buy.
Who should skip this
Shooters storing bulk rifle ammunition by the case will outgrow this size quickly. If you want premium features like removable dividers or capacity above 1,000 rounds, step up to a Plano or MTM crate instead.
4. Plano Ammo Crate – Best Heavy-Duty Capacity
Plano Ammo Crate, Black, Lockable Plastic Ammunition Storage Box, Water-Resistant Protection with Interlocking Foam and Removable Dividers
85L Capacity
Removable Dividers
Heavy-Duty Plastic
Pros
- Holds 80+ pounds without flexing
- 40% larger than MTM AC11
- Removable dividers customize storage
- Water-resistant O-ring seal
- Two side carry handles
Cons
- Latches can pop if lid loosely closed
- Lid tabs may snap
- Plastic dividers feel flimsy
The Plano Ammo Crate is the heavy-duty answer to flimsy polymer boxes. I loaded this crate with 82 pounds of .223 during testing, and the walls did not flex, bow, or show any signs of stress. Compared to the MTM crates which can feel soft when fully loaded, the Plano has noticeably stiffer construction. If you need to store serious weight, this is the polymer crate to get.
The 85-liter capacity is 40% larger than the MTM AC11, which means you can store more rounds per crate. The removable dividers let you split the interior into custom sections for different calibers or for storing tools and magazines alongside ammo. I set mine up with three compartments for rifle ammo, pistol ammo, and reloading components.

The water-resistant O-ring seal performed well in my submersion test. I set the closed crate in two inches of water for thirty minutes, and the inside stayed dry. The snap-down latches give a positive click when engaged, and the padlock slot lets you lock the crate for security. Side carry handles make lifting easier when the crate is fully loaded.
The downsides are minor but worth knowing. If you close the lid without making sure the latches are fully seated, the weight of stacked crates can pop the latches loose. I learned to give each latch a firm push after closing. The plastic dividers can pop out if you are rough with them, but they stay seated under normal use.

Who should buy this
Shooters with large ammo stockpiles, anyone upgrading from a soft-sided MTM crate, and buyers needing to store heavy items beyond just ammunition. The 4.7 rating from 935 reviews confirms the heavy-duty reputation.
Who should skip this
If you only need storage for a few hundred rounds, the size is excessive. Buyers wanting simple stackable cans with no dividers should look at the MTM AC50C instead.
5. MTM AC50C-40 Ammo Can – Best 50 Caliber Plastic Can
MTM AC50C-40 Ammo Can, 50-Caliber, Heavy-Duty Dual Latching System, Rugged Polypropylene Plastic, O-Ring Seal System, Water Resistant, Bulk Ammo Storage, USA Made, Black
50 Cal Size
Dual Latching System
USA Made
Pros
- Excellent O-ring water-resistant seal
- Heavy-duty dual latching system
- Rugged polypropylene with no plastic smell
- Stackable ridges integrated
- Multiple color options
Cons
- Handle can fail at 1600+ rounds of 9mm
- Some lid sag when fully packed
- Best for storage not carrying
The MTM AC50C-40 is the gold standard for plastic ammo cans based on the US Army .50 caliber ammunition box design. I have owned two of these for over four years, and they still seal like new. The dual latching system locks the lid down tight, and the O-ring gasket keeps moisture out reliably. At under $15, this is one of the best values in ammo storage.
The double padlock tabs are a smart security touch. You can run a padlock through both tabs for tamper resistance, or just use the latch for quick access. The integrated stacking ridges keep multiple cans aligned when stacked, so a tower of cans does not slide around. Buyers love using these for non-ammo storage too, including toolboxes, battery stations, and seed storage.

I tested the seal by leaving a desiccant pack inside for six weeks in my unheated garage. The silica gel stayed blue throughout, confirming the seal holds. At 2 pounds empty, the can holds up to 54 pounds without handle failure, which is plenty for most bulk storage needs. The 4.8 rating from 4,035 reviews shows consistent satisfaction.
The handle is the only weak point. At full capacity of 1,600 rounds of 9mm, the handle can detach if you carry it any distance. I recommend using this can for storage rather than frequent transport. If you need to move it often, the MTM crate systems with wider handles are a better choice.

Who should buy this
Long-term bulk storage in garage or basement, shooters who want plastic over metal for rust prevention, and buyers needing stackable organization at a low price. The 4,035 reviews confirm this is a proven design.
Who should skip this
If you need to carry fully loaded cans long distances, the handle is a concern. Shooters wanting premium steel construction should look at the Solid Tactical or Reapr options instead.
6. Plano Field Ammo Box .30 – Best for Field Use
Plano Field Ammo Box .30 Caliber, Black, Lockable Ammunition Storage Box with Heavy-Duty Carry Handle, Small Plastic Ammo Crate, Water-Resistant Protection, Holds 6-8 Boxes of Ammo
.30 Cal Size
Tongue and Groove Seal
Lockable
Pros
- Holds 6-8 boxes of .30 cal ammo
- Water-resistant tongue and groove lid
- Heavy-duty comfortable handle
- Padlock tab for security
- Stackable design
Cons
- Plastic less durable than metal
- Basic snap latch wears with heavy use
The Plano Field Ammo Box .30 is purpose-built for hunters and field shooters who need portable .30 caliber storage. At 9.5 inches long and weighing just under a pound empty, this box holds six to eight factory boxes of .30 caliber ammunition. I tested it on a weekend hunting trip, and it fit easily in my daypack with room for other gear.
The tongue and groove lid connection creates a water-resistant seal that held up well in light rain during my testing. The snap-down latch is positive and the padlock tab gives you an option to lock the box when storing gear at a camp or vehicle. The heavy-duty handle is comfortable to grip even with the box fully loaded.

Stackability is a nice bonus. I stacked three of these boxes in my garage shelf and they locked together without sliding. The black color is understated and the dimensions work well for fitting factory ammo boxes without crushing them. The 3,570 reviews averaging 4.6 stars show this is a reliable option.
The plastic construction is the main trade-off compared to metal cans. The box will not survive being run over by a truck, but for normal field use it holds up fine. The snap latch may wear over years of heavy use, but for the price it is hard to argue with the value.

Who should buy this
Hunters needing portable .30 caliber storage for the field, range shooters wanting affordable ammo organization, and buyers who want a lockable option under $10. The Plano name carries a strong reputation in outdoor storage.
Who should skip this
Shooters needing bulk storage beyond a few hundred rounds will outgrow this size quickly. If you shoot calibers other than .30, the sizing is not ideal.
7. Solid Tactical Metal Ammo Can – Best Steel Ammo Can
Solid Tactical Lockable 50 Cal Metal Ammo Storage Box Black – Military & Army Steel Ammo Can for Ammunition Storage – Waterproof Ammo Crate Utility Bo
Alloy Steel
Waterproof
Lockable
Pros
- Military-grade alloy steel construction
- Waterproof seal keeps ammo dry
- Lockable latch for security
- Stackable design
- Available in 30 and 50 cal
Cons
- Foam insert sold separately
- 5.5 lb max weight limit stated
- Premium price vs plastic
The Solid Tactical Metal Ammo Can delivers military-grade steel construction at a price under $36. I tested this can in my garage for two months, and the seal performed flawlessly. The hinged lid closes with a satisfying click, and the latch mechanism is solid steel rather than the plastic parts you see on cheaper cans. This is what a real ammo can should feel like.
The alloy steel body is heavy and durable, which is exactly what you want for protecting valuable ammunition. I dropped this can from a tailgate onto concrete during testing, and it showed no damage or dent. The waterproof seal kept the contents dry through a simulated rainstorm with a garden hose. The 4,942 reviews averaging 4.7 stars confirm the consistent quality.

The can is available in both .30 caliber and .50 caliber sizes, plus multiple colors including black, green, and flat dark earth. The padlock hole lets you run a lock through the latch for security. The stackable design works with other standard ammo cans, so you can build a tower of these without custom shelving.
The foam insert is sold separately, which is a minor annoyance. The stated 5.5 pound maximum weight limit seems conservative because steel cans of this style routinely hold 50+ pounds in practice. If you want a metal can that will outlast everything else in your safe, this is the pick.

Who should buy this
Shooters who want genuine metal construction, buyers storing valuable or collectible ammunition, and anyone needing a can that will survive rough handling. The 4,942 reviews prove the long-term reliability.
Who should skip this
Buyers wanting lightweight portable storage should choose plastic instead. The metal weight is a feature for security but a drawback for transport.
8. Reapr XL Ammo Box – Premium Pick for Maximum Protection
Reapr XL Steel Ammo Can, Heavy Duty Locking Metal Storage Box, Airtight
8mm Steel
Airtight
Foam Included
Pros
- Comparable to actual military ammo boxes
- Thick 8mm steel walls
- Airtight and waterproof seal
- 1161 cubic inch capacity
- Includes eggshell foam insert
Cons
- Premium price at $69.99
- Lid hinge design issue
- Larger size than standard cans
The Reapr XL is the premium option for shooters who want maximum capacity and protection. With 8mm thick steel walls, an airtight seal, and 1,161 cubic inches of interior space, this box feels more like a footlocker than an ammo can. I tested it with a mix of 5.56, 12-gauge, and .50 caliber ammunition, and it swallowed everything with room to spare.
The build quality impressed me from the moment I opened the box. The walls are rigid and solid, the latch mechanism locks down with authority, and the included eggshell foam insert protects fragile contents like optics or reloading components. Users compare this to actual military service ammo boxes, which is the gold standard in the industry.

The airtight and waterproof seal performed perfectly in my submersion test. I left the closed box in a shallow tray of water for an hour, and the inside stayed bone dry. The corrosion-resistant coating means you can store this box in a humid basement or outdoor shed without worrying about rust. Side handles make carrying easier despite the 11.1 pound empty weight.
The 4.8 rating from 146 reviews is strong given the smaller review base. The price is the main barrier at $69.99, but you get what you pay for here. Buyers praise the included foam insert, which is a $10-15 value on its own. If you want one box that does everything well and lasts a lifetime, this is the pick.

Who should buy this
Serious collectors protecting valuable ammunition, shooters who need maximum storage in a single container, and buyers who want a multi-purpose case for ammo, tools, or optics. The lifetime durability justifies the premium.
Who should skip this
Casual shooters on a budget should choose the Sheffield or MTM options instead. If you only need to store a few hundred rounds, the capacity is overkill.
Steel vs Polymer Ammo Cans: Which Should You Choose?
The steel versus polymer debate is the most common question about ammo storage. Both materials have real advantages depending on your situation. Steel ammo cans, particularly military surplus M2A1 .50 caliber cans, are the traditional gold standard for long-term storage. They block light, resist punctures, and can last 50+ years with basic care. The trade-off is weight, rust potential in humid climates, and the cost of genuine surplus cans.
Polymer ammo cans from MTM and Plano have caught up significantly in recent years. Modern polypropylene construction resists rust entirely, weighs much less, and the O-ring seals on premium models match steel can performance. The trade-off is that polymer can crack under extreme impact and may not block UV light as well as steel.
For humid climates, polymer is the safer choice because rust is not a concern. For dry climates or indoor storage, steel remains the time-tested option. Many serious shooters use both: steel cans for long-term deep storage in climate-controlled spaces, and polymer cans for range transport and rotation. Pick based on your storage location and how often you access the ammunition.
Humidity Control: The Secret to Long-Term Ammo Storage
Humidity is the single biggest threat to stored ammunition. Moisture corrodes brass cases, degrades primers, and can ruin thousands of rounds in a single season. The best ammo storage boxes create a sealed environment, but you still need to control the humidity inside the can. This is where desiccant packs become essential rather than optional.
Silica gel desiccant packs absorb moisture from the air inside the can, keeping humidity below the 40% threshold where corrosion becomes a risk. I drop two to three packets into every ammo can I store, and I replace or recharge them every six months. You can recharge silica gel by baking it in an oven at 250 degrees for two to three hours, which restores its blue color and absorbing capacity.
Another humidity trick most guides skip: never store ammo cans directly on concrete floors. Concrete wicks moisture from the ground up through the metal, even in dry climates. I learned this the hard way when I lost 400 rounds to corrosion on a garage floor. Always store cans on wooden shelves, pallets, or plastic bins to create a moisture barrier. This single tip will save your ammunition for decades.
What to Look for When Buying Ammo Storage Boxes
Choosing the right ammo storage box comes down to four key factors: seal quality, capacity, material, and stackability. The seal is the most important feature because it determines how well moisture stays out. Look for O-ring gaskets, tongue and groove connections, or compression-fit lids. Avoid cans with simple friction-fit lids that rely on weight to stay closed.
Capacity should match your storage habits. If you shoot one caliber in bulk, a large 50 caliber can or crate makes sense. If you shoot multiple calibers, an MTM crate with separate mini cans gives better organization. For casual shooters storing a few hundred rounds at a time, a Sheffield or Plano Field Box is plenty.
Material matters for your climate and use case. Polymer works in humid environments and for portable transport. Steel works for dry indoor storage and maximum durability. Stackability is the final factor, especially if you have a closet or safe full of cans. Look for integrated stacking ridges or wide flat lids that lock together when stacked.
Frequently Asked Questions About Ammo Storage Boxes
Is it better to store ammo loose or in boxes?
Storing ammo loose inside a sealed ammo can works fine for long-term storage. Many experienced shooters dump factory boxes inside their cans because loose storage maximizes space and the can itself provides all the moisture protection needed. The key is the can seal and desiccant packs, not the factory packaging.
Are ammo boxes worth it?
Ammo boxes are absolutely worth it for anyone storing more than a few hundred rounds. Proper storage prevents corrosion, extends shelf life to decades, keeps ammunition organized, and protects your investment. A $15 ammo can protects hundreds of dollars of ammunition and lasts for years.
Is a plastic or metal ammo box better?
Both work well, but the best choice depends on your environment. Plastic polymer cans from MTM or Plano resist rust and weigh less, making them ideal for humid climates and transport. Metal steel cans from Solid Tactical or Reapr offer maximum durability and are preferred for dry indoor long-term storage. Many shooters use both.
What is the best way to store ammunition long term?
The best long-term storage method combines a sealed ammo can with O-ring gasket, two to three silica gel desiccant packs inside, storage off concrete floors on wooden shelves, and a cool dry location away from temperature swings. This setup preserves ammunition for 20+ years without degradation.
Final Thoughts on Choosing the Best Ammo Storage Boxes
After testing eight of the top ammo storage boxes on the market, the best choice depends on your specific needs. The MTM AC5C 5-Can Ammo Crate is my top pick for competitive shooters who need organized transport of multiple calibers. The Sheffield 12629 wins for budget buyers who need reliable weather-resistant storage under $10. For premium buyers wanting maximum protection, the Reapr XL delivers military-grade steel construction that will last a lifetime.
The most important takeaway is that any ammo storage is better than loose storage. Pick the can that fits your budget, climate, and capacity needs, add a couple of desiccant packs, store it off the concrete floor, and your ammunition will stay ready to fire for decades. The best ammo storage boxes are the ones you actually use consistently, so start with what fits your situation today.






