The question "Can a .308 shoot a 7.62?" is a common one, often leading to confusion. The short answer is: no, not reliably and safely. While the two calibers appear similar, and some ammunition may seem interchangeable, attempting to fire 7.62x51mm NATO ammunition in a firearm chambered for .308 Winchester (7.62x51mm) can result in serious damage to the firearm and injury to the shooter.
.308 Winchester vs. 7.62x51mm NATO: Subtle but Significant Differences
The confusion stems from the close relationship between the .308 Winchester and the 7.62x51mm NATO cartridge. Both are roughly the same diameter (.308 inches) and use similar-sized cases. However, subtle differences in cartridge dimensions, particularly in the case head and neck, exist. These seemingly minor variations can have catastrophic consequences.
Key Differences Leading to Incompatibility:
- Case Head Dimensions: The 7.62x51mm NATO cartridge has a slightly larger case head diameter than the .308 Winchester. This means a 7.62x51mm round might not fully seat in a .308 chamber, causing dangerous pressure build-up.
- Case Neck Dimensions: Differences in case neck dimensions also contribute to potential problems. The 7.62x51mm NATO round might not be consistently held in the chamber of a .308 firearm, leading to unpredictable firing and a risk of the round moving or even exploding upon firing.
- Chamber Tolerance: .308 Winchester chambers are typically manufactured to tighter tolerances than those designed for 7.62x51mm NATO rounds. This tighter tolerance further exacerbates the risk of dangerous pressure buildup when firing the slightly larger 7.62x51mm NATO round.
Case Studies and Safety Concerns:
There are numerous anecdotal accounts and reports of firearm damage stemming from attempting this seemingly minor swap. In many cases, the rifle suffers damage to the chamber or bolt face. In extreme circumstances, the weapon itself can fail catastrophically. This isn't a theoretical risk; it’s a real-world danger. Always prioritize safety and never attempt to fire ammunition of one caliber in a firearm designed for another.
Why the Confusion Exists?
The near-identical ballistic performance of the two calibers contributes to the misunderstanding. Both cartridges produce similar bullet velocities and energies at comparable ranges. This similarity leads some shooters to mistakenly believe they are interchangeable.
Misinformation and Internet Myths:
The internet can be a breeding ground for misinformation. While some sources might suggest the cartridges are effectively the same, this is a dangerous misconception. Always verify information from reputable sources before making any decisions about your firearm and ammunition.
The Safe Approach: Stick to Specified Ammunition
The only reliable way to avoid problems is to always use the ammunition specifically designed for your firearm. Check your firearm's manual for the recommended ammunition type and always visually inspect the cartridges before loading and firing.
Ammunition Labeling: Pay Close Attention
Always pay attention to the markings on the ammunition boxes. The caliber will be clearly indicated. Don't rely on visual similarities alone; confirm the exact ammunition type with your firearm's specifications.
Conclusion: Safety First
While the .308 Winchester and 7.62x51mm NATO rounds might appear similar, they are not interchangeable. Attempting to use 7.62x51mm NATO ammunition in a .308 Winchester firearm is unsafe and can lead to serious damage to the weapon and injury to the shooter. Always prioritize safety and only use the ammunition specifically designed for your firearm. This is not an area where taking chances is acceptable. The potential consequences are far too severe.