I was given several hundred rounds of this 7.62x51 ammo.
All boxes are sealed, dated the same and, have a blue ripcord.





Of the 20 rds in the box;

14 headstamped: 20-73
5  headstamped   5-73
1  headstamped   8-73

All are 'Boxer' primed, and have the same Boat-Tail bullet.

Well, the writing is Hebrew so my guess is that it is Israeli in origin.

Yep, it's Isreali

yn is the one headstamp of Israel Miliary Industries.  Note the first two big letters on the box and the headstamp on the cartridge.  (I've no idea how to make a backwards y and upsidedown n to simulate the Hebrew letter.)

It's 7.62mm NATO.  The boat tailed bullet may, or may not make it more accurate.  US 7.62mm NATO is normally blunt tail.

Let us know how it shoots, it's 30 years old.

-- Chuck