Hi Chromeed, the stiffest mag spring around is outt'a the 06/70 Mauser Parabellum magazines... I'd try one of these mags before all else.. and if it works, then we can see if we can find a busted bottomed mag and rob the spring out of it!...

.. we can make it work one way or another.. just have to start somewhere.. best to you, til...lat'r....GT.....