Picked up a crate of this the other day because it was too cheap to pass up. Dont know exactly what it is. I can't read German, maybe someone on here can. I assumed it was German 8mm. Headstamp is P249 S* 14 38. Posted it on one of the FB milsurp groups and one guy said it was proof ammo. If thats the case, its pretty much useless right?