Don’t you love it when things just make sense? When people name things in a way that’s intuitive?
Like calling that delicious treat a “cookie” (sorry, UK - “biscuit” is what you put sausage gravy on for breakfast).
Good news! While not always the case in the gun world, the difference between rimfire vs centerfire cartridges is actually quite intuitive.
There are lots of terms that can be a source of confusion (like when you heard about a pistol being “out of battery” for the first time but were pretty sure that there are no actual AAA’s involved…?).
With the quick breakdown below, you can intelligently participate in the next range-day debate about rimfire vs centerfire cartridges.
What Does “Centerfire vs Rimfire” Even Refer To?
“Centerfire” or “rimfire” refers to the way the firing pin in a gun strikes the tail-end of a particular cartridge. This propels the bullet forward out of the gun.
Fundamentally, the two processes function in a similar manner: When you pull the trigger, the firing pin inside the gun hits the primer. This creates a mini-explosion that ignites the gunpowder, sending the bullet at the head of the cartridge down the barrel.
What is Rimfire Ammo?
When you shoot rimfire ammo, the process described above occurs with the firing pin striking the outside edge (rim) of the back of a cartridge. Rimfire rounds have priming compound (powder) placed all around the base that explodes when activated by the pin.
This cartridge made its debut in the .22 caliber size, and they have remained popular in this measurement, especially for long rifles.
Rimfire is low in power, but also low in recoil as compared to its modern center-fire cousin. Some shooters, therefore, prefer this cartridge type for its high accuracy potential at the range or when hunting small game.
Additionally, rimfire may be the exclusive ammo option if you decide to become a connoisseur of antique rifles.
What is Centerfire Ammo?
The firing process for a centerfire cartridge is the same, but with the pin striking the middle of a round instead of the edge. There are several advantages to this design.
Centerfire rounds appeared about twenty-eight years after the rimfire cartridge was created. A self-contained primer inserted into the rear of a round exploded the centerfire cartridge onto the scene (pun intended).
This spiffy update eliminated some problems for ammo manufacturers--and created others.
Particularly, rimfire rounds required a spinning process to uniformly distribute priming explosive into the rim. This step intended to avoid “playing roulette” with which segment of the round the firing pin in the gun would contact.
The new self-contained primer erased the need for this process, but the metal jacket on cartridges of the day needed reinforcing. It was not strong enough to contain the abundance of firepower that could now be packed behind a bullet.
It was some time before ammo makers were able to improve the metallurgy to optimize the potential of the centerfire round. Eventually, the result was a cartridge with significantly higher velocity and far more reliability than its rimfire counterpart.
Is One Better Than the Other?
Whether one is “better” than the other largely comes down to how applicable either type is to your shooting needs.
For the average shooter who wants the most “bang-for-your-buck” (in terms of firepower) and to have the best chance of ammo being available, centerfire rounds might make the most sense. Plus--especially if you want to squeeze every penny out of their value--these cartridges can even be reused!
If you’re a collector of rare pieces that were made before centerfire stepped on the scene, or you just think life should have less recoil, a .22 long or short rimfire round is sure to delight.