How does rimfire work ?

When you research to buy a rifle or pistol, have you ever come across listening to the word “rimfire”? Yes, rimfire used to define the type of ammunition a particular firearm uses. With the experienced hunters or military, they may toss these terms around loosely and with confidence. However, for starters, they have no ideas to control them.

In this article, we will show how does rimfire work that you can use them as masters.

How does 22 rimfire work

How does 22 rimfire work

1. Rimfire Structure

Rimfire structure

Rimfire structure

As mentioned previously, rimfires are one type of cartridge. They also include three separate parts: detonators, propellants, and warheads. Now to understand how does rimfire work, we will dig deep to to structure of a rimfire.


Unlike the more common center-fire, where there is a separate primer kept in the base of the cartridge case and the rim is solid. Detonators of rimfire were placed in the base’s rim. Then the firing pin of a gun strikes and crushes them to ignite the gunpowder and fires the bullet.So, the rim of the rimfire cartridge often extends and widen.

rimfire composition

rimfire composition


The next section of the cartridge is considered the ‘main engine,’ propellants, contains brass casing and powder. Brass casing requires a thin case and its diameter up to .44 (11 mm) was once common while propellants used black powder. However, to generate much higher pressures, modern rimfire cartridges spend smokeless powder. Rimfire calibers become smaller to 22 calibers (5.5 mm)

When the powder burned, it creates repulsion to push the warheads out of the gun to the target.


The first part of rimfires is a block of metal. Which can help bullets through meat or other materials?This is a very important part that affect how does rimfire work.

2. Types of Rimfire Ammunition?

So, how many type of rimfire ammunition? The most common kind is the .22LR (long rifle):

  • .22 Long Rifle (LR): Most common used in the world and used for many shooters.
  • .22 WMR: Winchester Magnum Rimfire. Used for hunting and is between the .22LR and the .223 centerfire round.
  • .22 Short: Not too popular. Mounted in some revolvers
  • .17 HMR: Hornady Magnum Rimfire. Newer round that is  more powerful and flatter shooting than the .22LR
  • .17 HM2: Hornady Mach 2: smaller than the .22LR but higher power. The Smaller brother of the HMR.

3. What happened while rimfires were burned?

Bullets are designed relatively safely until they were shot out of the barrel. When the trigger was pulled , the firing pin of a gun strikes and crushes the base’s rim, activate the detonator. Then ignite explosive detonator in the ‘main motor.’ In this process, we will undertstand very clearly about how does rimfire work.

When explosive chemicals were burned, they generate a huge amount of gas. The pressure of this gas will push warheads flying at the speed of lightning, about 300m / s.


The chemical explosion of a rimfire is designed to not explode immediately. This could be dangerous to the lives of people shot. Instead, they are designed relatively slow blast, so it should move very smoothly bullets from the gun.

Then fire explosives faster, creating a multi-thrust. When the bullets are out of the gun, the gun will jerk back under the basic physical laws (law of motion of Newton).

When bullets fly out of the gun, the pressure from the explosion is released suddenly. That makes the gun play “bang bang.” It’s similar to when you open a bottle of wine at a fast speed and high pressure.

4. How does rimfire move?

We usually think the bullets fly perfectly in straight lines, but not quite unrealistic. Bullets were taken some different force when it flew through the air. At close distance, the bullet almost moves in a straight line. At greater distances, they move in a slightly curved downward path due to gravity.


Air resistance, power spinning, gyroscopic force of the bullet is also very complex. When all these factors were put together, they will make the bullet flying in a complicated orbit in the air.

5. How does rimfire destroy?

Due to the fast-moving, so energy bullets also have great dynamics, generated by explosive combustion of bullets.

how does rimfire destroy

how does rimfire destroy

Bullets have enormous destructive power when they transfer their energy to the target. The quicker momentum these objects lose, the greater force it generates. A rifle bullet flew to the target in 1/10 seconds can generate a force equivalent to a heavy-duty truck rested for 10 seconds. Imagine being struck by a truck; you will understand why the bullets have such explosive force.

6. How far the bullets fly?

Speeds of rimfire always fluctuate and depend on upon several factors such as Gravity, projectile’s size and air resistance. So a rimfire works quite complicated right?

Gravity makes a projectile down toward the earth while in flight. The projectile’s size and the air energy affect the speed by which it travels. Air drag slows the speed of a bullet and reduces the distance by which it flys.

The velocity of a bullet is calculated by feet per second (fps) in the United States. The 0.22 rimfire cartridge has a very small powder charge, so the rimfire’s velocity is between 370 m/s and 460 m/s.


7. Economics

Rimfire cartridges are not typically expensive,  due to the inherent cost-efficiency of the ability to the in large lots. The price of ingredients used in the cartridges (lead, copper, and zinc) increased in 2002; the prices of the ammunition then further increased in 2012. The price is between 2$ to 30$. It depends on the type of ammunition and number of tablets per box.

You can find it at online shops or stores for hunters.

8. What kind of shoot is rimfire used of?

Rimfire is used for both gunshot and rifle due to different purposes. Some popular guns on the market today can be called such as Browning® Buck Mark Semiautomatic Rimfire Pistols; Ruger® Double-Action .22 Revolvers;  Smith & Wesson® M&P .22 Compact Rimfire Pistol; etc. The price of which is not similar and depends on the shape, material, and power.



Rimfire is a useful tool for hunters and soldiers. In another word, it will be very helpful when being used for the right purpose. However, it is not for playing so that you should consider before using them. Hope that you have understand how does rimfire work!

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