SR-12

I read Marcus Luttrell's book "Lone Survivor" while deployed to the location he was in...from the way the book read I thought it was used more as a Snper style weapon. Any thoughts or education for me? There is a Company here in Texas that makes a weapon similar to his and they call the line of stuff Team-10 as a memorial to the SEAL Team.

I would just like some info on the weapon in question as I have never heard of it before.

TG