Tanaka M40A1 Gas Sniper Rifle (Cartridge Type Version 2)
1/1 Scale High Performance Gas Powered

Bolt Action Sniper Rifle w/ Full Metal Bolt System
Polymer Body With Rubber Stock Pad
With 5 Cartridges (each can hold 1x BB Bullet)
With 20mm Picatinny Rail on Top of Receive
Bipod stub is ready to install any generic bipod

Adjustable HopUp
Sling mount can be installed with any sniper rifle sling

With an M40 in your collection, you can outfit as a sharpshooter in pretty much any military or law enforcement branch type from the US and many other western countries and it would be technically acceptable as correct.