Even Ruger does not recommend ammunition not manufactured to US specs (see page 12 in their manual), which is probably standard lawyer speak CYA... but could very well be performance related and/or safety advice.
My mini30 is one of the older makes and its a hit or miss proposition using the russkie or chinese ammo my SKSs & AKs love.
Tagged to see what response new Mini30 owners have to say.
A free people ought not only to be armed and disciplined, but they should have sufficient arms and ammunition to maintain a status of independence from any who might attempt to abuse them, which would include their own government." - George Washington, January 8, 1790, First State of the Union Address