AABB KOO Defense Glock Carbine Kit for KSC & Marui G17 GBB

No instructions supplied, assembled intuitively enough though with the photos online to assist.

On the 18C model, the rear sight screw of the pistol inside the slide needs to be removed to gain access to the semi/auto selector. Remove the selector plate and tiny spring. Rotate the selector to full auto and remove the selector. Replace with the low profile AABB selector and reassemble the selector plate, spring, sights and screw. Check the action.

Sliding the pistol into the carbine body using the pistol accessory rail is tricky and the pistol tends to try to rise up out of the rails. Firm pressure on the body of the carbine by tightening the quick release latch at the front a little is needed, a shot of silicon helps as well to get it to slide in straight and no end up with the barrel pointed upwards once its in. Use the TM writing on the side of the pistol body as a guide to whether or not the pistol is sliding into the carbine straight or not. The writing should sit level just below the carbine body. This will make sense as you hold the carbine and pistol in your hands.

I luded up the cocking handle piece to aid low resistance on the slide to ensure it fires repeatedly smoothly. Noticed on the odd shot out of 50 the slide would not go fully forward. A tap on the cocking handle then fired the chambered round/BB. Be wary if this to avoid accidentla shots. Luding and working the mechanism should free it up.

The cocking handle itself is hopeless. It bent in the first 10 cocks and then stripped out 5 cocks later. A longer thread shaft and real steel instead of recycled Ali would solve this. In the interim I have fitted a long threaded bolt with some rubber fuel line over the bolt to use as a makeshift handle.

Make sure ALL the allen bolts you see are checked for tightness, as all mine were loose. Not a problem, just remember to tweak them all up before using the weapon.

Lube and work the foldaway stock a few times and you'll get the technique required to fold and deploy it quickly. It was awkward at first but then quite easy once I got the right grip.

The foregrip is flimsy feeling but seems to work fine. It has a hidden handle extension as well which is quite trick.

Shooting, its very solid and made the pistol very accurate AND presice, with good long range repeatable groupings of shots.

It DOES make the pistol louder though, which some may find bad, but for CQB, I like as it makes targets jump and hesitate up close and sneaky.

Overall... I like it. It needs modding to make it great but as is, for the price, its decent enough so far.