Today on an extra special episode of Historical Intermediate Calibers, we’ll be taking a look at one of the most controversial experimental military rounds, one that many believe should have become the standard for the Western World at the beginning of the Cold War. That round is the .280 British, also known as the 7x43mm, and beginning in 1947 it competed head-to-head against the caliber that eventually became the 7.62 NATO in trials to become the standard infantry small arms caliber of the free world. The .280 British has, in the almost 70 years since its invention, become one of the great “might-have-beens” of the small arms ammunition world. Many small arms enthusiasts wonder how firearms history might have been changed if this brilliantly designed British 7mm round had been adopted by NATO instead of the overlarge and too-powerful US-designed 7.62mm.
I found your essay today, May 2025. Anyone who looks into the .280 soon understands the global politics involved as well as the military stubbornness.
I was part of a wildcat project not too many years ago that modernized the.280 Brit. We increased the shoulder angle several degrees and developed loads for a 2.25” version that would fit in an AR15. With 120 and 130gr commercial bullets it was superior to the 7.62x39 in a 20” barrel. Seating the bullet further out for a “proper” 2.55” OAL in a bolt gun with a parallel throat gave outstanding accuracy and the velocity could be increased 200fps or a bit more without excessive pressure or recoil. This is a wonderful deer hunting round in the same ballpark as the old .300 Savage. We didn’t have any steel helmets to shoot at, but we found accuracy at 800 yards to be more than good enough.
The original later .280 with 140gr bullets and the powders of the era “failed” because it wasn’t a.30-06. Military stubbornness.
I found your essay today, May 2025. Anyone who looks into the .280 soon understands the global politics involved as well as the military stubbornness.
I was part of a wildcat project not too many years ago that modernized the.280 Brit. We increased the shoulder angle several degrees and developed loads for a 2.25” version that would fit in an AR15. With 120 and 130gr commercial bullets it was superior to the 7.62x39 in a 20” barrel. Seating the bullet further out for a “proper” 2.55” OAL in a bolt gun with a parallel throat gave outstanding accuracy and the velocity could be increased 200fps or a bit more without excessive pressure or recoil. This is a wonderful deer hunting round in the same ballpark as the old .300 Savage. We didn’t have any steel helmets to shoot at, but we found accuracy at 800 yards to be more than good enough.
The original later .280 with 140gr bullets and the powders of the era “failed” because it wasn’t a.30-06. Military stubbornness.
Drew458