What you have there is 5.6mm GP90 (Gewehrpatrone 90) at least if this picture is accurate:



If so, it's Swiss (not Swedish) standard issue military ammo probably manufactured by RAUG Munition.  It's possible that RAUG sent some to Swedish military units and you have the overflow.  That would be unusual, however.I've gone through tens of thousands of rounds of it over the years.  It is, indeed, OUTSTANDING ammo for reliability and accuracy.  In this area there may be no one better than RAUG.

It's probably less than idea for self defense.  The Swiss design military ammo so it won't fragment- a side effect of their rather over anal interpretation of restrictions on expanding bullets in international law.

Regardless, EVERYONE should try a little bit of this stuff.  It makes outstanding target ammo.

See also: Q. What is the best round for match use?

This guy did go to the factory:
www.cybershooters.org/swiss_ammunition_enterprise.htm

What did they do that even after switching back to a copper jacket it still wont fragment? How thick is that jacket? It doesn look that odd in the pictures in the above page...

Quoted: Tatjana - This form is great, lots of really good info.  I just read your new FAQ - a real down to earth manual on 223 ammo - best I've seen anywhere - congrats.  I was wondering your opinion on this GP90 used for defeating auto glass and 10ga. metal.  It appears it will have great penetration. It's a lot less expensive than Federal trophy bonded bearclaw.

I don't know the gage or the range these were shot at but take a look:


from www.cybershooters.org/swiss_ammunition_enterprise.htm