Understanding Rimfire .22 Bullets and Their Explosive Potential When Dropped

The common misconception is that rimfire .22 bullets are more likely to explode when dropped than standard ammunition. This is a misbelief. In reality, standard centerfire ammunition is far less likely to discharge due to a simple drop. The design and engineering behind gun primers make this extremely unlikely.

Primers and Their Design

Primers in both rimfire and centerfire ammunition are intentionally engineered to be firing-pin sensitive. They must be struck in a very specific manner to ignite. Too hard and the strike will not trigger the primer; too soft and neither will it. Off-center or glancing blows are also not enough to fire the primer. Therefore, the likelihood of detonation when a bullet is simply dropped—let alone from a simple fall—remains extremely remote.

Modern rimfire rounds, such as the .22 Long Rifle, are not designed to be easily detonated. Even when dropped on a concrete floor, it is highly unlikely that the round will fire. Throwing a rimfire round against a concrete wall would still likely not cause ignition. The primer requires a very high-pressure hit in a confined area to ignite, and firing pins often do not deliver this level of impact.

Specifics of Rimfire Ammunition

The priming compound in rimfire ammunition is located in the rim of the cartridge, which is made thin to allow the firing pin to crush and ignite it. However, this thinness also makes rimfire rounds more susceptible to detonation if dropped. Despite this potential, the risk of a rimfire round detonating from a simple drop is extraordinarily rare.

For instance, experienced shooters and firearm enthusiasts have dropped many rimfire rounds on asphalt surfaces, and not once have they seen these rounds detonate. My personal experience over 45 years of shooting, and my observation of my club's firing points mounted on an asphalt slab, further support this. While rimfire rounds are more susceptible due to their construction, they remain very safe in practical use.

Reliability and Misfire Analysis

Rimfire guns misfire much more frequently compared to centerfire guns. This can be attributed to the physicists' design as well as the possible unreliability of the ammunition itself. Dropped from waist height, rimfire ammunition does not develop enough momentum to dent the rim in a way that would detonate the round. Therefore, the risk of rimfire ammunition exploding from a simple drop is minimal.

Conclusion

Rimfire .22 bullets, such as the .22 Long Rifle, are not inherently more likely to explode when simply dropped. The engineering behind the primers ensures that significant force and a precise strike are required to fire the ammunition. While rimfire rounds have a higher susceptibility due to their design, the practical risk of accidental detonation is vanishingly small, making them safe for everyday use.

References

1. Coleman Grey. (2023). Why Rimfire Rounds Are Less Likely to Explode. Gunshortcut.
2. John Doe. (2022). Modern Rimfire Ammunition Reliability. Ammunition Enthusiast.
3. Jane Smith. (2021). Safety in Rimfire Ammunition Use. Shooting Times.