Are you using the correct piston? Sound like you are firing light loads with the heavy piston? Either way, these Turkish guns need some rounds through them to loosen up.
All these Turkish made SA guns - Tristar, Weatherby SA line, Mossberg SA line, Hansen (plus many other off brand names) are pretty much the same and many are even made in the same factory.
They aren't the best quality, but then again they don't cost $1,500 either. I will say Weatherby does have the best support after the sale.
I have had about 10 of these SA shotguns in total, have about 5 now. They have all been as good as any Remington or Browning I have owned. I have seen the occasional jam/miss feed.. but no more than any Remington, etc.