Supposedly the Finnish Army used more captured weapons than they did of their own. However, in their case, they had already standardized on the 7.62x54r, so there was no problem there. But their handgun was (officially, anyway) a .30 cal. Luger. They had no Soviet pistol rounds in their supply system. So although captured weapons were highly prized, especially submachine guns, when the ammo ran out, they passed them back to the rear troops, which they were supposed to do to begin with.
One of the more interesting oddities of captured weapons during WWII concerns the standard handgun of the Norwegian Army. After the end of that campaign, the Germans disarmed the Norwegian Army. The standard Norwegian pistol was a Colt .45 automatic. So some Colt .45 automatics wound up being used, somewhere at least, by the Germans. Then, in an even stranger twist of hisory, at the end of the war the Germans still in Norway were disarmed by the Norwegians. The Germans were equipped handgun-wise with Lugers, the story goes, and those Lugers remained in use until replaced by--wait for it--Glocks. Also, the Norwegians retained the original leather holsters that came with the Lugers but modified them with a U.S. style wire hanger so they could be used with a U.S. style pistol belt.
A footnote to the story is that the Norwegians exprimentally produced an additional batch of .45 autos, probably 30 years ago now, as a cost study and the resulting pistols were sold on the surplus market.
Shoot low, sheriff. They're riding Shetlands!
Underneath the starry flag, civilize 'em with a Krag,
and return us to our own beloved homes!
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