Ammo cans aren’t just for storing bullets anymore. These military-grade steel containers protect everything from tools to emergency supplies. But choosing the right size matters.

Getting the exact dimensions helps you stack them properly, fit them in storage spaces, and know exactly how much gear they’ll hold.

Popular ammo can sizes include the compact 30 cal, versatile 50 cal, spacious Fat 50, specialized 40mm, and industrial 20mm. Each comes with its own NSN (National Stock Number) proving military authenticity. The steel gauge thickness ranges from 0.9mm to 1.2mm depending on the can size.

30 Cal and 50 Cal Ammo Can Size Comparison

30 Cal (M19A1) Dimensions and Capacity

The 30 cal ammo can measures exactly 10 inches long, 3.5 inches wide, and 7 inches tall on the outside. Inside, you get roughly 9.5 inches of usable length and 3 inches of width.

This compact military container holds approximately 1,200 rounds of 9mm ammunition when loaded loose. For boxed ammunition, expect around 800 to 1,000 rounds. The hinged lid design with tension clamp makes one-handed opening easy.

At just 4 pounds empty, it’s the most portable option for range days. The M19A1 designation appears on authentic military cans, along with the NSN 8140-00-828-2938. Many users prefer this size for first aid kits, electronics storage, and vehicle emergency supplies.

50 Cal (M2A1/M2A2) Dimensions and Storage

The 50 cal ammo can is America’s favorite. It measures 11 inches long, 5.5 inches wide, and 7 inches tall externally, giving you significantly more room than the 30 cal version.

This versatile storage container holds 800 rounds of 5.56/.223 ammunition or 400 rounds of 7.62. The M2A1 and M2A2 models differ slightly, but both offer the same external footprint. Empty weight sits around 5 pounds, making it still portable when loaded reasonably.

Fat 50 (PA-108) Size Specifications

The Fat 50 ammo can gives you 12 inches length, 6.75 inches width, and 8.5 inches height. That extra width and height make a huge difference for storage capacity.

Originally designed for linked 5.56 SAW ammunition, this wider military container handles bulkier items. It weighs approximately 7 pounds empty but can store 25-30% more than a standard 50 cal can. The PA-108 designation marks authentic military Fat 50s.

Large Format Ammo Can Dimensions (40mm and 20mm)

40mm (PA-120) Ammo Can Measurements

The 40mm ammo can stretches 17 inches long, 5.5 inches wide, and 10 inches tall. Its unique shape makes it ideal for long, narrow items like tools and equipment.

This specialized military container originally held 32 rounds of 40mm grenades for the MK19 grenade launcher. The completely removable lid sets it apart from hinged designs. Two side-mounted carrying handles distribute weight evenly when loaded.

Civilian applications include storing long rifles, fishing rods, camping equipment, and workshop tools. The narrow profile fits in tight spaces while the height accommodates taller items. Some versions carry the PA-120 or BA30 designation with NSN 8140-01-446-1584.

20mm (M548) Heavy-Duty Can Size

The 20mm ammo can is the beast of the family. External dimensions reach 18.5 inches long, 8.25 inches wide, and 14.375 inches tall. Inside, you get 17.5 inches of usable length.

This industrial-grade container holds up to 1,500 rounds of 7.62 or 5.56 ammunition. The M548 designation marks authentic military versions with NSN 8140-00-739-0233. Empty weight approaches 15 pounds, but the dual side handles make carrying manageable.

Other Dimensions: Arizona Tea Can Size Dimensions

FAQ’s

What size is a 40mm ammo can?

The 40mm ammo can (PA-120) measures 17 inches long, 5.5 inches wide, and 10 inches tall. This narrow, tall design originally stored 40mm grenades for military grenade launchers.

What size is a 20mm ammo can?

The 20mm ammo can (M548) is the largest standard size at 18.5 inches long, 8.25 inches wide, and 14.375 inches tall externally. Internal dimensions provide approximately 17.5 inches of usable length.

What are the dimensions of a 556 ammo can?

5.56 ammunition typically comes in standard 50 cal (M2A1) ammo cans measuring 11 inches long, 5.5 inches wide, and 7 inches tall. These cans hold approximately 800 rounds of 5.56/.223 ammunition.

How big is a 30 cal ammo can?

A 30 cal ammo can (M19A1) measures 10 inches long, 3.5 inches wide, and 7 inches tall on the outside. The compact size makes it perfect for portability while still holding 1,000+ rounds of pistol ammunition.

How wide is a 50 cal ammo can?

The standard 50 cal ammo can is 5.5 inches wide. The Fat 50 variant (PA-108) increases width to 6.75 inches for extra storage capacity.

Is a 30 cal bigger than 9mm?

30 caliber refers to bullet diameter (0.30 inches), while a 30 cal ammo can is a storage container. The 9mm bullet (0.355 inches) is actually slightly wider than .30 caliber. However, a 30 cal can is much larger than individual 9mm rounds and holds over 1,000 of them.

Is a .40 bigger than a 9mm?

Yes, .40 caliber bullets measure 10mm in diameter, making them wider than 9mm bullets. The .40 S&W cartridge is also slightly longer, taking up more space in storage containers.

How many 9mm fit in a 30 cal can?

A 30 cal ammo can holds approximately 1,000 to 1,200 rounds of 9mm ammunition when loaded loose. If you keep ammunition in factory boxes, expect around 800 to 1,000 rounds depending on box configuration.

What are the 4 types of ammo?

The four main ammunition categories are rimfire (like .22 LR), centerfire (most rifle and pistol rounds), shotshells (shotgun ammunition), and specialty rounds (tracer, incendiary, blanks). Alternatively, ammunition types include full metal jacket (FMJ), hollow point, soft point, and armor-piercing designs.

Conclusion

Choosing the right ammo can size comes down to three factors: what you’re storing, where it’s going, and how often you need access. 30 cal cans excel at portability, 50 cal cans offer versatility, and larger formats handle bulk storage.

Most shooters need a combination of sizes. Start with two 50 cal cans for range ammunition, add a 30 cal can for pistol rounds, and consider a Fat 50 for long-term storage. Authentic military surplus provides unmatched durability at reasonable prices.