Ultra light, ultra fragile - Fostech AR-15 Mg/Al Alloy Upper Receiver Stripped

I have no idea what sort of chinesium grade scrap metal this is made out of. But it weighs practically nothing. The upper parts kit weighs more than it if not just as much. But this comes with a trade off.

This is the most fragile upper receiver I have ever seen. Tightening the muzzle break caused the index pin the shear into the upper. I applied probably as much force as one would use trying to crack open a cold one to put the muzzle break on. Noticing that it had bottomed out, and the crush washer wasn't even starting to compress and wanted to turn more, I decided to take it off. This is when I noticed the WHOLE BARREL WAS TURNING. Bracing the barrel in my bare hand I was able to get it off just fine with little to no force. I decided to take the barrel nut off to inspect what was going on... Trying to take off the barrel nut caused BOTH lugs to break right off. This isn't even 20ft pounds of force. I had applied maybe 45ftlbs to put it on... and this just shattered like cheap pot metal with even less than that to remove it.

Looking at other reviews this thing is prone to cracking with the slightest bit of force. And looking at how and were this broke it clearly has air bubbles in the casting.

More interesting is when the barrel was going into the upper it had a TREMENDOUS amount of play to it. I highly doubt it would have ever held a zero.

I would never trust this thing for anything. Not even a good paperweight. I honestly would trust one of the plastic upper receivers more from omni as they actually hold up to some forces being applied to it.