Can't say that I've ever seen those projectiles, but there's only so many cases of Tok ammo a guy can buy.
It has the ‘bxn 53’ brass casing that Sellier & Bellot factory produced so much of for Czechoslovakia in 1953, but I am used to seeing those with a copper-plated steel jacket over a lead core, not your shiny bullet heads.
The lacquered steel cases will be marked ‘aym’ (a factory on the Slovak side), and have plated steel jackets with lead and a mild steel core. You can see the differences below:
Usually a green Czechoslovak surplus case of ammo can have either bxn, aym, or a mix in it, and you don't know until you crack it open. The cardboard boxes inside are brown with aym, and white with bxn. All on 8-round clips. All corrosive primers. The steel are a bit less desireable, because the core will ricochet (but many ranges won't allow either, because they both have steel jackets).
Now your silver bullets, are they actual nickel jackets like you said, or just un-plated steel? Are they magnetic? Can you cut them with side cutters or a Dremel cut-off wheel, and then is it a pure lead core, or does it have a steel slug inside?
The Cu plating isn't just there for show; it helps cushion and lubricate the projectile as it explodes through the barrel, being a softer metal. Having direct steel on steel (or nickel) contact will wear out the rifling more quickly, will it not?
Think some were imported as converted automatics by Century.
