mg3 top cover problems

[blckwlfny]

i ave a semi 42 with a cam roller stud feed stud on the bolt. I have een using an MG! top cover and feed tray. It was functioning fine through about 10K (blank) rounds
Then i went to using an MG3 top cover with my MG1 feed tray to take advantage of its return spring and hold open hinge

first problem: the "wings" that hold the feed tray on to the top cover pin broke off of the tray
second problem: then, at one reenactment, the feed stud (roller cam) snapped off the bolt

I would like to keep using the MG3 top cover, but has anyone else had these problems?

Thanks

[JBaum]

I have to wonder if the receiver of your gun is a tiny bit short in the feed tray area and things are getting battered.