Thank you for sharing your knowledge and experience. The marauder pistol in carbine form is the one I'm planning to work on this time. I'm affraid that it's loading/magazine plasement near the middle if the breach will prevent me from being able to use the one piece adjustable rails you recomnended. I may try to regulate, if that's the same as clocking or rotating the barrel to get it to shoot into crosshairs of optically centered scope.