These mags of Bren are compatible with Aks and vice versa as i had seen Ak mags in Bren-2 iirc
Bren 2 taking AK mags hhmm this one ?
That is a dedicated receiver for that with AK style paddle magazie release for making Bren 2 work with AK standard mags
^such kits virtually exist for many convertible firearms, FN SCAR, various AR (CMMG MK47 lower receivers)...
Besides here is Bren 2 STANAG-compatible magazine in 7.62x39mm (that MCIWS magazine in same calibre must be very similar in geometry to this one), both sides
^upper part of magazine is cleary STANAG one-straight, has knotch on left side for magazine locking tab and so, notice no AK mag locking lug on its rear or knotch on front.
So very unlikely this mag would go in any AK,it'll just drop outta rifle...
...and here is standard Bren 2 receiver trying to take in standard AK mag
welp, seems
impossibru without performing
khatnaa of that AK mag