In the early 50s, the British attempted to introduce the .280 British intermediate round, alongside the EM-2 bullpup assault rifle and Taden light machine gun. Apparently there was some interest on the Continent and in the Commonwealth, but in the end, the project was canned as the Americans absolutely refused to go with anything smaller .30-06 and the British government decided that standardizing ammunition within NATO was more important than introducing some neat guns.
Nevertheless, the eventual selection of 7.62x51mm ammunition was not without its opponents - mostly those saying that it was too powerful for the kind of mid-range, rapid-fire suppression tactics foreseen on the "modern" battlefield, not to mention heavy...and those opponents were shown to be mostly correct as the US adopted the 5.56 AR-15 family as their main assault rifles a scant decade after the introduction of 7.62.
What would it take for the British to run ahead with the .280 anyway (probably known ITTL as 7mm)? If they do, it's very likely the FN will join the bandwagon (OTL they were pretty enthused about it), and of course that cements the 7mm's role as an important round in the grand scheme of things. Would a more ascendant/less obviously falling apart Empire/Commonwealth do it? Would a greater French role? Can a British-French-Belgian bloc force the introduction of the .280 instead of or alongside the .308 Winchester? Is the only possible influence an internal American one, causing the Americans to somehow reduce their complaints and agree to standardize on the British round? Somehow, I get a feeling that American jingoism may prevent a willingness to use any kind of foreign-origin round, regardless of actual concerns (e.g., even if 7.62 is decided to be too strong, they'll instead prefer to standardize on a 6.5mm round based on the .270 Winchester or something.
Nevertheless, the eventual selection of 7.62x51mm ammunition was not without its opponents - mostly those saying that it was too powerful for the kind of mid-range, rapid-fire suppression tactics foreseen on the "modern" battlefield, not to mention heavy...and those opponents were shown to be mostly correct as the US adopted the 5.56 AR-15 family as their main assault rifles a scant decade after the introduction of 7.62.
What would it take for the British to run ahead with the .280 anyway (probably known ITTL as 7mm)? If they do, it's very likely the FN will join the bandwagon (OTL they were pretty enthused about it), and of course that cements the 7mm's role as an important round in the grand scheme of things. Would a more ascendant/less obviously falling apart Empire/Commonwealth do it? Would a greater French role? Can a British-French-Belgian bloc force the introduction of the .280 instead of or alongside the .308 Winchester? Is the only possible influence an internal American one, causing the Americans to somehow reduce their complaints and agree to standardize on the British round? Somehow, I get a feeling that American jingoism may prevent a willingness to use any kind of foreign-origin round, regardless of actual concerns (e.g., even if 7.62 is decided to be too strong, they'll instead prefer to standardize on a 6.5mm round based on the .270 Winchester or something.