The gentlemen above have it quite right, apart from my own status regarding divinity.
Savage had a big contract to supply the Number 4 but, once the war got going, people were screaming that the contract was against the Neutrality Act, even though the Brits were paying in gold. Prior to the state of emergency, the US could build anything for anyone; in theory, Adolf could have had Mausers built by Remington, although he definitely would have had a hard time getting them back to Germany. FDR ran through a law so that US military equipment which was surplus to the needs of the US military for the defence of America, could be sold. This is where those 50 famous "old destroyers" come in: they were 1918 and 1919 ships and they were fully-reconditioned, definitely not junkers. The ships were traded to Britain for US military bases in Empire countries; the American base at Goose Bay is, I think, the last one still operating. But Britain ran out of money. But FDR had the law in place now. So the US Amy adopted the Number 4 Rifle and forgot to buy any ammo. The rifles kept being built for the US military and so marked. They also forgot to cancel the contract so Savage kept building the things. Ally-samey thing ammo: Navy adopted the .303 cartridge and discovered that they didn't have any rifles for the stuff...... so they "sold" it on the "surplus" market, "forgot" to cancel the contracts, Winchester kept crankin' it out and you still run into the odd round today. Once Lend-Lease was fully in place, there was no need for this kind of shilly-shallying and so we could get on with the War.
People might criticise the Americans for not getting involved in the War until 2 years after we were in, but actual events show that the US military, and the US Administration, were very much ahead of public opinion. And, we must remember, FDR had an election to fight in 1940.... and he was also fighting a Press which was very much opposed to many of his Socialist initiatives. He even had to worry about strongly pro-Nazi diplomats in his own service: Joseph P. Kennedy is an excellent example there. BUT FDR was on our side and so was the military. And so the training aircraft.... and even a few fighters..... "disappeared" mysteriously when they were parked along the Canadian border, the rifles and the ammunition kept on being built...... and, finally, Lend-Lease came through.
At least, that's how it was explained to me.
As to the rifle, it is an interesting specimen but, for that price, it had better have Roosevelt's AND Winston's fingerprints all over it!
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