7 x 66R : Eley ; .280 Flanged Nitro-Express, hollow point
priming cap : attachment : press fit
Reference: Barnes, F C : 1972 : Cartridges of the World : Digest Books Inc : : p 213. Description: a rimmed bottlenecked version of the .280 Rimless Nitro Express, introduced for single shot and double barreled sporting rifles. It was one of the first successful modern high velocity small bore cartridges, and enjoyed a considerable if brief vogue in the years before the First World War. It initially gained its reputation as a hunting round because of its evident 'knock-down' effect on thin skinned game, but this began to sour when it was used on more dangerous game, which, if not killed outright, on occasion turned on the hunter with fatal results. Within its limitations, it was a very good cartridge.