Well that abortion of a charging handle that looks like a shitty clone from an HK roller-lock rifle appears to be steel. Steel is a harder METAL than the aluminum that the rail is made of. I'm guessing that wear is going to always exist with that design. Normal charging handles exhibit wear in the locking notch as well.

I agree, that sounds like a bogus rifle. Get a direct gas gun from Colt or BCM. Save yourself some money and headaches.