head stamp identification

[1911canoe]

I have a couple boxes of 7.62 x 51 with the following headstamp, FNM 81-47 then the nato circle and cross. can anyone tell me where it was manufactured, and if it would be corrosive?

 

[PerversPépère]

I think it's Portuguese but I wouldn't put my hand in the fire for this.
PP.

 

[sunray]

Hi. The maker not on the boxes?
FNM was used by Fábrica Nacional de Municiones, Santa Fe, México, Fábrica Nacional de Munições de Armas Ligeiras, Chelas, Portugal and another unkown Mexican plant.
If you're lucky it'll be Portugese made in 1981. Portugese ammo isn't corrosive, but you'd best treat is as if it is and clean accordingly.
Go here for headstamp codes.
http://cartridgecollectors.org/headstampcodes.htm

 

[tiriaq]

Century Arms imported a large quantity of Portuguese FNM ammunition. Brown, 20 rounds boxes. Its good ammunition.