7,62×51 NATO Vs .308 Win: What’s the difference?
7,62×51 NATO Vs .308 Win: What’s the difference?
¿Is it safe to use NATO in your .308 Win Rifle?
Ammunition 7.62×51 mm NATO was introduced by US in the M40 rifle at the end of the 50s, and although today it is still used in other rifles like M240 or the M60. The impossibility of using that caliber in some countries and a nimble commercial market facilitated the development of a new caliber, this is how Winchester launched the .308 caliber for the first time in 1952, which has now become one of the most popular calibers.
Even though the Sports Arms and Ammunition Manufactures’ Institute (SAAMI) does not consider it unsafe to fire the commercial round in weapons chambered for the NATO round, there is significant discussion in this regard due to 3 main reasons:
1- The pressures generated are different in each caliber.
2- Thickness of the cartridge cases.
3- The size of the cartridge is different.
Here we have the primary problem. The 7.62×51 NATO caliber has longer chambers than the commercial caliber. That’s because of machine guns, some slack is necessary for fast feeding and ejection process. So, the solution is to lengthen the space of the chamber headspace.
In summary, we could work with the pressure differences and the thicker brass, but the main problem we have is in the chamber headspace. The length of the chamber must match the length of the cartridge. If the cartridge is too long, the bolt will not close or, what is worse, you will try to close it and it will be stuck in the chamber, a potentially dangerous situation. If the projectile is too short, it will suffer an excessive stretch when it is fired. At best, your brass will not last as long as it could, but in the worst case, you will experience inconsistent ignition and blown primers. Plus, if you reload ammo, you will know the 7.62×51 NATO caliber will not generate the same pressure because of the thickness of the cartridge cases.
In addition, we add a reason 4:
4- Guarantee. The problems of non-commercial use are not covered by the guarantee of the rifle manufacturers.
The Bergara rifles are designed for maximum precision and performance. Therefore, the manufacturing and the assembly lines, verify and measure adjusting the space of the head of each unit of rifles produced. Thanks to that process, our rifles guarantee a sub-MOA grouping at 100 yards with commercial ammunition, a differential value that has made the Bergara rifles and barrels known throughout the world.
CONCLUSION:
As we have seen it is possible to shoot with both calibers, but we expose ourselves to certain risks and loss of guarantee. It is up to you to choose, but from Bergara we recommend use .308 Win. in our .308 Win rifles. For your safety and for your rifle’s.
For more information, do not hesitate to contact our technical assistance department: [email protected]