@ Pblatzz: yes, same standard. Portugal also got a bunch of machine-guns at the same time, these being converted Dreyse 1918s modded for air-cooling and to handle the new-type belts and so forth. The Nasties had converted these for training their own Army with a more-or-less modern machine-gun, then sold them to Portugal as MG-34s became available. IIRC, this was the MG-13 in German service. Beautiful old guns but, living as we do in a Free Country, they are, to us, VERBOTEN. I do believe that Portugal got a supply of German ammo right at the beginning, then set up to make the same ammo.
Portugal's problem in the Great War was that they had German-made rifles and no factory, German-purchased ammo and no ammo factory. When they declared war on Germany in 1914..... those nasty, unfriendly Gemans refused to sell them any more bullets! Or rifles, for that matter! Some folks just have no sense of ha-ha, it seems. RESULT was that Britain supplied the Portuguese Brigade (actually a Battalion)with SMLEs, tin hats, Lewises, Vickers Guns, artillery and everything else. This kept up right through the war, even after the Portuguese Brigade became the Portuguese Division (actually a Brigade). Tomfoolery with formation names was a face-saver: Portugal was Britain's oldest ally, dating from the time of Prince Henry the Navigator.... but it was also just about completely non-industrialised and it was likely the poorest participant in the War. They didn't have modern equipment because they didn't have the money to buy it, but they were willing to help a 400-year-old ally anyway. Gotta respect that.
Following the conversion of the Mauser-Vergueiro rifles, Portugal got a shipment of Kar 98k Mausers from Germany at fire-sale prices. These were ex-Wehrmacht rifles, at least in part, specially finished and very specially marked, many with Mauser COMMERCIAL markings: just beautiful things to behold, big eagle-and-swastika markings on the butts. Reason for the fire-sale prices is that Hitler was trying to get Salazar on his side. Portugal stayed neutral in the Second War, which took guts all by itself: their ONLY contiguous neighbour was Fascist Spain which was more-than-just-a-little-bit pro-Nazi. Lisbon was the European terminus of Condor flights from South America, not to mention being for 6 years the Spy Capital of the World. I knew a B-25 pilot who made it back to England through Portugal following upon a soujourn in a 14th-Century dungeon in Spain.... even stole back the P-38 he borrowed from a Gestapo agent who didn't need it any longer.
Portugal used a mix of .303 and 7.92x57JsS until well after they converted to 7.62 NATO, started selling off their surplus in the late '70s. The FNM 7.92 ammo was just beautiful stuff and it packed one heck of a wallop. Accurate, too. Heavy enough load that it made a '42 run at astounding speeds, although it toasted the brass.
I know this meanders and maunders and likely muddles as well, but I do hope it helps a bit.
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