G&G CM16 Magazine Compatibility Issue

[McKay1912]

Hey guys so Ive got an issue with my recent purchase. So I purchased the E&C metal 70 rnd magazines and im having issues. Im not 100% sure but they might be to tight. They wont lock in and require a good smack/bump to get them to lock in. Also the mag release becomes crazy stiff.

Im wondering if its the compatibility or if there is anything I can do to fix the problem. I imagine smacking/bumping them in with some force is bad for the magwell and gun.

Any help is definitely appreciated as I paid about $75 for a 5 pack.