You can kinda see the rib in the back,, they lock in just fine, I'll post a range report when I get a chance to shoot them.
Edit- they have no stamps or any markings that would suggest their origin.
LCpl Williams, Evan T. USMC-R, 02-08-2010 ~
D Co, 4th CEB, Engineers UP!! OEF 21JUN-20SEP2011
REV. 19:11 And I saw heaven opened, and behold a white horse; and he that sat upon him was called Faithful and True, and in righteousness he doth judge and make war.