Echo1 M28 Sears/Mag problems

Hey guys, I recently picked up a friends semi-new Echo 1 M28. He had succumb to the slam fire problem, and attempted to fix it with a new trigger box and sears set from ASGI. Installed it all correctly, but it still slam-fired.

Once i got it, I bought the new 300% Cylinder set from EHobby Asia and fully fixed the slam firing, but now Ive run into a new problem.

When i pull the bolt back, the first sears wont catch the metal piston. And with the brand new metal piston, i know it has to be the sears. I was wondering if anyone has had a similar problem and would know how to fix it?


And the other issue is that i recently bought 4 KS mags (same as the plastic E1 mags, except metal) and Ive been having a few feeding issues, where when I pull the bolt back, it will load 4-6 bbs into the area where the cylinder is. But it doesn't do it every time, just randomly. Any idea why it would do that?

Any help is appreciated, thanks guys.