Do Blasters Ever Run Out Of Ammunition?

They do. Blasters draw on compact power packs that hold energy and, in Legends, a charge of blaster gas. A standard E-11 power cell is good for around a hundred shots, and a plasma cartridge for more than five hundred, which is why nobody in a firefight is seen swapping one out very often. The real limit on a blaster is not ammunition at all. It is heat. (Ultimate Star Wars; The New Essential Guide to Weapons and Technology)

Where the misconception comes from#

Nobody reloads. Across nine films of running gun battles, characters empty weapons into stormtroopers, bounty hunters and each other without once stopping to change a magazine, and the natural conclusion is that blasters simply do not need one. (A New Hope; The Empire Strikes Back)

That is a reasonable read and it is wrong. The weapons carry ammunition, it is just measured in hundreds of shots rather than the ten or twenty a slugthrower magazine would give you. A trooper with a plasma cartridge who fires thirty rounds in a corridor fight has used about six percent of it. There is no reason to show a reload, because in practice one rarely happens mid-engagement. (Ultimate Star Wars)

What is in the pack#

In Legends the ammunition is gas. Blaster power packs, also called energy packs, carry a small electrical store and a charge of compressed tibanna gas, which the weapon energises into a bolt. (The New Essential Guide to Weapons and Technology)

That last part matters more than it sounds. The gas is a commodity, and Legends sourcebooks count hundreds of different blaster gases in use across the galaxy, with tibanna the best known. What goes into the pack is a supply question, not just a technical one. (Cracken's Rebel Field Guide; The New Essential Guide to Weapons and Technology)

The gas trade is real economics in this galaxy, not set dressing. Bespin exists as a going concern because tibanna gas is worth harvesting out of a gas giant's atmosphere and refining in floating complexes like Cloud City. Whole worlds are built around getting gases out of the sky and into containers. (The Empire Strikes Back; Ultimate Star Wars)

Capacity in practice#

The numbers quoted for the E-11 are about a hundred shots from a standard power cell and more than five hundred from a plasma cartridge. The E-11 blaster rifle is the workhorse of the Galactic Empire, carried by essentially every stormtrooper in the galaxy, so that figure is the baseline most firefights are working from. (Ultimate Star Wars; A New Hope)

Carrying spares was normal. A soldier with a couple of extra packs is not thinking about ammunition as a constraint on a single engagement, only across a campaign. That is the difference between blaster warfare and the projectile warfare of most other settings: resupply is a logistics problem rather than a tactical one. (Ultimate Star Wars; The New Essential Guide to Weapons and Technology)

Packs did fail, though, and the failures were mundane. During the Battle of Hoth in 3 ABY, a Rebel private named Emon Kref was fighting with an A295 blaster rifle whose power pack kept falling out. His solution was tape. Somewhere in the Rebel Alliance's finest hour, a man was holding his rifle together with adhesive while AT-ATs came over the ridge. ("Beyond Hope")

The actual limit#

Heat is what stops a blaster, not an empty cell. (The New Essential Guide to Weapons and Technology)

Blasters are prone to overheating, sometimes badly enough to destroy themselves, and sustained fire will take a weapon out of action long before the pack runs dry. Every bolt heats the part of the mechanism that energises the gas, and the weapon needs time to shed it. Fire long enough and the blaster becomes a very expensive club. (The New Essential Guide to Weapons and Technology)

This reframes how blaster combat actually works. The constraint is not how many shots you have, it is how fast you are allowed to spend them. Suppressing fire, holding a corridor, laying down volume to pin an enemy in place, these are all things a blaster is bad at, because the weapon will cook itself before the ammunition matters. It is a weapon that rewards accuracy and short controlled bursts and punishes anyone treating it like a machine gun. (The New Essential Guide to Weapons and Technology)

Which explains a lot about how firefights look across the saga. Everyone takes cover, everyone shoots in short bursts, and nobody hoses a room down for thirty seconds straight. That is not choreography. That is people who know what happens to a hot blaster. (A New Hope; The Empire Strikes Back)

Follow the two limits through and they point in opposite directions. Ammunition is a supply-chain question, solved by carrying more packs and by having someone bring crates of them to the front. Heat is a per-weapon question that no amount of logistics fixes, because it happens in the hands of the person shooting. (Ultimate Star Wars; The New Essential Guide to Weapons and Technology)

That is why a squad's problems change shape depending on how long the fight lasts. In a short engagement nobody thinks about either constraint. In a long one, the trooper who has been laying down fire is the one whose weapon quits, while the trooper conserving shots still has a working blaster and most of a pack left. (The New Essential Guide to Weapons and Technology)

So the short version#

A blaster holds hundreds of shots, and the person carrying it is likely to have more packs in a pouch. Running dry is possible and it does happen, but it happens across a long deployment rather than in the middle of a shootout. (Ultimate Star Wars)

The weapon that genuinely never runs out of anything is the lightsaber, which is one more reason the Sith and the Jedi have spent so long as the apex predators of this galaxy. Everyone else is managing a heat budget. (The New Essential Guide to Weapons and Technology)