The JG M4 CQB-R is by far one of the best M4 variants on the market today. This gun comes complete with a tight bore barrel, and 125 spring. It utilizes a version 2 all metal gear box, with metal gears. It also has a full metal spring guide and a poly carbonate piston head. The 10.5 inch barrel is designed for CQB work, but I added an SRA Armament suppressor to mine. This gun shoots flat and straight right out of the box, and works best with .25-.30 gram bbs. It has an effective range of 125-150 feet, but with the hop up it can hit targets out to 200 feet with the right ammo.
I totally love this gun and wouldn\'t trade it for any other out there,