Ideally I would put the diameter at between 4.6 (the bare minimum as it were) and 5.5mm in terms of its overall preformance area.
Depending on the diameter of Aquis as 3-5 calibers in diameter.
The G11s muzzle velocity and its rate of fire are, at least in part, theoretical factors that boost the likelyhood of striking the target multiple times quickly, which makes up for a less-than-optimal terminal effect. Two is better than one, as it were.
Edit:


Its hard to find gun porn of a blocky rifle.
I wonder today if H&K were to release the G11 as a civilian rifle in semiautomatic only, with its fixed optic pre-zerod at ~300yds, how well ot would do.
Im pretty sure it would come down to ammo cost.





Credit for the original PMG goes to Robbe25.



