Madbull Daniel Defense licensed Outer Barrel 14.5inch (Government)(Steel version)

Is your aluminum outer barrel flexing and throwing off your shots while you use a bipod or a supporting hand on the foregrip ? ELIMINATE this flexing problem and increase your barrel stability with quality STEEL outer barrels by Madbull.

Features at a glance:

This version is designed for 9inch RIS rail or Forward Grip

Authentic Daniel Defense markings

Machined steel for realistic weight (heavier than aluminum barrel)

Phosphate finish, like real steel

Shortened CQB length 363-375mm inner barrel recommended

Includes 14mm CCW Threading for attachments

High quality Phosphate finished steel; Madbull makes some of the best outer barrels around and they offer them in a broad variety of lengths. A standard M16 has a 20 inch barrel while the standard M4A1 has a 14.5 inch barrel but the beauty of the M16 family is their ability to modify the length with a lot more options than that.
At a full M16 length of 20 inches, this is about as long as a barrel can be before you run into problems. Not just unwieldy lengths but if inner barrels stray to far beyond 510mm they run into volumetric problems as the standard Version 2 gearbox cylinder lacks the internal volume to fill such a large inner barrel and so starts to suffer from negative pressure causing a drop in performance.
So, in situations where you want maximum pressure to FPS efficiency and the tightest cone of fire you can get out of an AR platform then you really need to look no further than an M16s 20 inch barrel- unless you get a special bore up cylinder.