Just to clear things up. The GP P40 does have a steel chassis Insert. Very strong . The feed ramp is built into the chassis, not the barrel because the the barrel rotates obviously. Other than my old Megastar maybe, it's the lightest recoiling 10mm I've ever shot. And a tack driver!

Review: Grand Power P40 - Slovakian DA/SA Full Ambi Rotating Barrel Plastic Fantastic - The Firearm BlogThe Firearm Blog