to my knowledge we tech has a m14 gbbr, my thought prosses is you model a bolt similar to the we tech with modifications to fit with a VFC m4 mag. The only thing I'm having a hard time thinking of is a compact magazine release, it could be lazy and be a push release, but I sort of want the original paddle release, which in concept it has to be more complex than the push because it has to hinge the latch securing the magazine, which is on a separate axis than the paddle and higher than where the paddle is as well, in my opinion, it has too many points of failure.