Magpul MOE M-LOK Hand Guard, Carbine-Length (MAG424)

The Magpul MOE M-LOK Hand Guard (MAG424) replaces the two plastic halves on an M4-pattern carbine with Magpul's reinforced, heat-resistant polymer and adds M-LOK accessory slots at the two, six and ten o'clock positions. It is a drop-in: each half's rear flange sits under the existing delta ring and its front flange seats in the handguard cap behind the front sight base, so there is no barrel nut to change and no gas block to remove. Magpul lists it at 6.8 oz, 7.1 in overall and 6.6 in mounting length, 2.2 in wide and 2.5 in tall excluding the lip.

An integral riveted aluminum heat shield lines the halves, and a front lower lip with side extensions keeps the support hand off a hot front sight base. A relief cut at the top rear clears optic mounts that overhang the front of the receiver. The lower half carries raised cells with vent windows, and the upper half has ports along the top.

Because the halves are held by the delta ring and the cap, the handguard rides on the barrel. A sling under tension, a bipod, or a hand loaded against a barricade pushes on the barrel and can move the point of impact; a free-float rail that bolts to the receiver does not. For a fighting carbine at typical distances that shift is small, and the MAG424 adds M-LOK to a carbine that keeps its front sight base for far less than a free-float conversion. It needs a carbine-length gas system; Magpul makes mid-length (MAG426) and rifle-length (MAG427) versions for the other gas lengths.