Weatherby, Nosler, WSSM, RPM: Who Named These Cartridges and What the Name Promises
Big-game cartridge names credit a founder, a company, a marketing family or a design feature — and each tells you something different about the case.
The deer-rifle shelf carries more proprietary names than almost any other. Founders, companies, family brands and design acronyms sit side by side, and each kind of name points at a different fact.
Five conventions cover this set.
Named for the founder
240 weatherby ammunition and ballistics for 257 weatherby carry Roy Weatherby's name because he designed them; the same is true of the whole belted Weatherby line. A Weatherby name promises speed and, usually, a Weatherby rifle.
Named for the company
27 nosler carries Nosler's name as a proprietary cartridge — a bullet company's own case, launched in 2020 as the .277 member of a family that started with the .26 and .28. A search that attaches “rifle” to it is usually a shopper looking for the Nosler-built guns.
Named for a marketing family
243 wssm shells and 270 short mag both belong to Winchester families coined in the early 2000s: Short Magnum and Super Short Magnum. The phrasing that spells out the long name is the family name written in full. The initials describe the case shape, not the bullet.
Named for the man who wildcatted it
hornady 257 roberts ammo credits Ned Roberts, who spent the 1920s necking the 7x57 down to .25 before Remington standardized his work in 1934. The phrasing that puts a maker's name in front points at that company's factory load for it.
Named with a number that means velocity or lineage
25-35 follows the old Winchester Center Fire convention — bore then original black-powder charge — the same pattern as the .30-30 it was introduced beside in 1895. 25 creedmoor bullets follows the newest convention on the list: the parent case's name with the new bullet in front.
Named for a rifle company that never made the case
264 win mag for sale carries Winchester's name honestly — Winchester designed it in 1958 — and 284 ammo does too, for a 1963 case built around Winchester's own lever and autoloading rifles. Both are the company's designs, not just its loadings.
Cartridge naming varies by manufacturer and era; always match the exact designation stamped on your rifle before ordering ammunition, and confirm current stock and any state shipping restrictions before checkout.