WHAT DOES AK4D MEAN?

would I buy a Ptr? I'd but I might check it then depending on accuracy I'd personally possible change the barrel out to Other folks I have sourced.the third alternative is my Vortex holo sight as well as vortex 6x magnifier combo which happens to be Commonly on my ar-15 rifle.would I buy a Ptr? I would but I might test it then dependant upon accura