Also, is the CA M14 EBR capable of pulling an m140 spring without upgrades to the motor, piston, shims, gears and bucking?
The A&K magazines will have a similar design to G&P. It may be a tight fit. You can either sand or try switching the outer sleeve with the Hicap outer sleeve. This worked on n my CA SR 25.G&P 170 round (BB) SR-25 magazine $20.00 G&P SR25 170rd Magazine for SR25 AEG
Ares 160rd SR25 magazine $17 ARES SR-25 Magazine (Black)
I don't know if they fit into the A&K SR25 but I didn't find any A&K '25 magazines at all. Now, why did they take them off the market? They seem to be mighty popular.