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What Are Gun Primers?

One of the most important innovations in firearms history is the self-contained metal cartridge. It is made up of four components: primer, bullet, bullet and powder. This information should be easy to recall for any hunter-ed student, as illustrations of the components of cartridges have been part of the curriculum for decades. The fact that each of these four factors have an impact on cartridge performance is something our new hunter may not be aware of. This applies to accuracy, reliability, and lethality. The poor kid is not to be criticized, but they probably don’t know what a primer does. This is not an uncommon situation for young hunters. The primer is one of the most difficult to understand among the four components of a cartridge. A major breakthrough in primer technology will make today’s high-quality ammunition even better.
Even the most enlightened reloaders, who can make a layperson’s eyes glaze as they explain the details of how a bullet is constructed or their method for preparing brass to precise standards to build it, are not likely to know much about the primers they use to fashion their ammunition.

Shooters are often asked to explain the role of a primer. They describe it as something like a match that light the powder at the end of the cartridge. Or, the spark of a spark plug inside a motor cylinder that ignites the compressed mixture fuel and air.

Both analogies are incorrect. The primer’s function is much more complicated than a matchlighting a fuse or spark plug firing.

We need to understand the chemical process that makes the volatile slurry between the primer’s cup & anvil. Primer compound is the most hazardous substance in firearms and ammunition manufacturing. Gunpowder is highly flammable and blue steel barrel chemicals are not something you want to swallow. However, improperly handled primer compound can leave nothing but a smoke crater. Each primer is protected in its box.

Modern primers use lead styphnate as the primary explosive. Barium nitrate acts as the oxidizer and adds oxygen. Tetrazene, a sensitizer, makes it easier to detonate the primer. The fuels are the remaining elements.

Each primer compound has its own specific ingredients. The general formulas of primer compounds have remained stable over the years, largely because ammo manufacturers–and more importantly, their customers-–refrain from altering any recipe that is not tried and true.

Primers must be consistent. Primers that don’t come off when hit with a firing pin, no matter how cold or dirty, can make shooters extremely cranky and unforgiving. Primarily, the primer must ignite the powder charge.

Primer technology is undergoing a revolution despite this conservative outlook. There has been much talk recently about high-performance bullets and powders. But the fourth member of our cartridge quartet has also seen some exciting developments.

Federal Ammunition engineers have created the latest generation of primers. Catalyst is the new primer and represents a significant improvement on traditional primer compounds in many ways.

We must first answer the above question before we can discuss the merits and benefits of Catalyst primes. What do primers actually do?

The Primer Event

A primer can be thought of as a miniature volcano or rocket engine. It spews hot, burning slag and mixes with gunpowder in a cartridge. This mixture has been created since the 1920s by mixing lead styphnate (the main explosive) with barium nitrate (an oxidizer that adds oxygen to your flame). These two elements make up about 80 percent in the primer compound. These fuels (16%) and a pinch of tetrazene (4%) are also added to the mix. This is a sensitizer, which means that the compound ignites when it strikes the primer cup.

The firing pin hits the base, which is a cup made of metal. The anvil causes the primer compound to be pressed by the firing pin, which creates friction that ignites it.

Did you know? Armory Reloading Shop have a wide range of primers for sale

This brief eruption lasts 200 to 1,500 microseconds. One microsecond is one millionth of an second.

The primer should ignite all grains of powder simultaneously in order to ensure consistency from shot-to-shot. It wouldn’t cause more pressure than is necessary to ensure that the powder inside the case doesn’t become too compressed, which could lead to less uniform ignition.

The world we live in is not perfect. We need to use more primer to ensure that the cartridge fires. The ideal situation is for the primer to explode and the flame and the hot metals to penetrate deep into the gunpowder column. This will help us achieve the chimeric goal to ignite each kernel of powder simultaneously. The slag can spread through the powder to transfer heat more efficiently to the propellant if it is able.

Some shooters prefer to use compressed powder charges for their reloads. The idea is that there will be less powder slop in the powder, which will result in consistent results. However, this can make it more difficult for the primer to do its job. Because the pressure wave from the primer can compress the powder column, making it harder for the flame and slag to penetrate.
A New Catalyst

The request of a large customer drove the development and production of the Catalyst primer, as with many other innovations in ammunition. The U.S. government wanted a primer that was duty-worthy and didn’t contain any lead or other potentially harmful metals. This was both for law enforcement and military purposes. Federal handed the project to Joel Sandstrom, one of its engineers who later invented Catalyst.

Aluminum serves two primary functions. The aluminum makes explosive nitrocellulose more sensitive and helps heat up bismuth. The bismuth oxide “oxide” adds oxygen to the reaction. The remaining 10% is a mixture of fuels, binding agents, and sensitizers.

Although there have been lead-free primers available for decades, they were not considered reliable enough to be used in duty ammunition. They have been reduced to training ammunition.

Federal was required to eliminate lead as a principal requirement for the project. However, the primer Federal created wasn’t the same as the current lead styphnate combinations, but it is superior.

Drew Goodlin is the senior director of technology for Vista Outdoor, which owns Federal Ammunition.

Catalyst is compatible with modern propellants. This means that it won’t cause powder to be degraded like other primers. Catalyst propels heavier metals and produces less pressure from gases into the propellent bed, making it better than any Federal primer system, even its highly acclaimed Gold Metal primers.

It is not a good idea to alter existing ammunition lines that have a reputation for reliability and quality. This is especially true when it comes primers. Federal plans to switch all its centerfire ammunition (rifle, pistol and shotgun) to Catalyst primers in the next five year.

Federal’s confidence in Catalyst is evident by this, more than any other. Will consumers also embrace Catalyst as enthusiastically? This primer is a great deal of credibility because different parts of the U.S. government have been using Catalyst ammo.

Catalyst, like all primers relies on three things to function: a fuel source and an oxidizer. Catalyst primers have chemical reactions that are quite different to those using lead styphnate.

Aluminum is the most intriguing part of Catalyst’s pie. It makes up only 10% of the mixture, but performs two distinct, yet complementary functions.

Aluminum reacts with explosives to make them more sensitive. Catalyst would have nitrocellulose as the primer compound, which accounts for about 20% of its total composition.

Aluminum reacts also with bismuth oxide (60 per cent of the primer). This is the same bismuth that’s in nontoxic shot, with a density similar lead. It creates what Federal engineer Sandstrom calls “thermite reactions,” which is a fancy term for when the aluminum heats up to make the bismuth super hot.

The bismuth is very hot and heavy and does a better job of penetrating propellant beds and transferring heat to ignite powder. The last 10 percent of Catalyst’s formula is made up of binders, fuels and sensitizers.

Federal can modify this new base formula to make the primer work with different ammunition types. This includes pistol calibers such as the.380 that use very little primer compound and magnum rifle cartridges or shotshells which use a lot more primer material to ignite their powder. Federal’s new technology is only possible because Federal follows a simple rule: Federal ammunition must go bang every time a shooter loads it. It also needs to aim the projectile exactly where it is being fired at.

Catalyst will be able to do this, and then we can confidently say that we have entered the next phase of ammunition technology. Even if the hunter-ed graduate isn’t fluent in primer terminology, it’s likely that they will be part of the new primer revolution when they tag the first deer.