What was the first 7mm Magnum?

.275 Holland & Holland

Q: Could you please settle an argument for us. One of my mates claims that the .275 Holland & Holland was the first 7mm Magnum, and another says it was the .280 Jeffery, but I am sure it was the 7x64mm Brenneke. Who is right?
Arthur Reynolds

A: Sorry lads, but you are all wrong! The .275 H&H dates back to 1912; the .280 Jeffery came along in 1915, and the 7×64 Brenneke in 1917. But the first 7mm Magnum was the .280 Ross circa 1907. It was originally called the .280 Ross-Eley, but in 1912 became the .280 Ross. The long, tapered case delivered a

velocity of 3047fps with a 140gn bullet. But the bullet diameter was .288 rather than the 7×57’s, .284 diameter which is the modern standard.

Nick Harvey

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The late Nick Harvey (1931-2024) was one of the world's most experienced and knowledgeable gun writers, a true legend of the business. He wrote about firearms and hunting for about 70 years, published many books and uncounted articles, and travelled the world to hunt and shoot. His reloading manuals are highly sought after, and his knowledge of the subject was unmatched. He was Sporting Shooter's Technical Editor for almost 50 years. His work lives on here as part of his legacy to us all.