Ok, Sniper Rifles first.
DSR-50
Caliber- 50.BMG
Role- Anti-Matieral Sniper Rifle
Used By: Various forces from Germany, Lexoumburg, Spain,( notably the GSG-9 from Germany)
Description: Derived from the 7.62 NATO variant. (I used the 7.62 for the Used By section.)
It's a basic bolt action, except it runs off a bullpup design( see MTAR, CHICOM,QBB, KSG, SVU, etc) but can be deceiving because it has a extra magizine holder in front of the trigger like most guns)