Range Drum 40mm (L9A1)

The range drum (3805) is optimised for the various natures of 40mm munitions currently available. The sight mounting rail is tilted slightly to the right from the horizontal to compensate for drift caused by the spin of the projectile. The range scale is graduated from 0 to 2000 m and is fitted with a GTLS on the range and zero lines to aid setting the range under low light levels.

The range drum is fitted with a quick release (QR) female dovetail mounting bracket, commonly referred to as a rail grabber; which allows rapid fitment and adjustment to the Picatinny pattern mounting rail on the bridge of the GMG soft mount.

The range drum is fitted with a top mounted sight rail with two side mounted rails for auxiliary equipment such as lasers and range finding equipment. All three rails conform to Mil Std 1913.

The range adjusting drum can be locked in any elevation providing exact range targeting and preventing inadvertent movement once the range is selected.

Technical Specification

Weight 1.6 kg


Pt No




Weapon Fit

HK GMG 40mm

Mounting Method

Mil Std 1913 Picatinny

Rail Qty


Rail Type

Mil Std 1913 Picatinny

Elevation Lock



0m – 2000m