The Firearm Blog

I have previously discussed the Ultimax 100 Mk4. This is the latest iteration of the Ultimax 100 design and is being entered into the IAR competition by General Dynamics, although it designed by Singapore Technologies Kinetics (STK).

Photos by SMGLee. Click to expand:

Quick Change Barrel

I like the design of the ambidextrous fire selector.

Compared to the Mk4 the Mk5 takes unmodified STANAG (M16) magazine, has quad rails and a bipod/foregrip rather than a separate bipod and foregrip.

I am not sure if the Ultimax 100 Mk4 100 round drum magazine will be made compatible with the Mk5. The Mk4 took modified STANAG magazines.

Ultimax 100 Mk 4


Ultimax 100 Mk 5

UPDATE: Defense Review has more info.

SayUncle blogged a video of this ulta-high capacity 150 round AR-15 compatible (STANAG) magazine: the Armatac Industries CL-MAG.

The CL-MAG™ offers for the first time a reliable and efficient 150 rd magazine for the .223/5.56mm rifle. Designed to fit NATO standard (STANAG-4179) rifles, the CL-MAG™ quickly converts a rifleman with a standard M4 into automatic support personnel. The 150 rd magazines have been routinely emptied through the standard AR-15 setup without weapon failure. (Ambient temperature starts). The flexibility of such force multiplication makes the CL-MAG™ the most dominant accessory for the AR/M4/M16 family of weapons.

I must say I don’t get it. If the magazine breaks you are stuffed unless you are carrying other magazines. For example you may have to carry a 150 round CL-MAG, as well as 3×30 round magazines. If the CL mag jams after 50 rounds you are now carrying 100 rounds less than you were a minute ago.
On the other hand the Singaporean 5.56 LMG, the STK Ultimax 100, the same people who make the CPW, takes STANAG magazines and currently uses a modified 100 round C-Mag. This would give it 50% more capacity and increase rate of fire. The added weight may even be beneficial (when being fired, not carried).

Photo from Wikipedia.

The Ultimax 100 is being marketed to the Marines. It is has very low recoil, takes standard M16 magazines and can be operated by one person.

The weapon in action: