Twist Rate for a Benjamin Marauder?

Twist rate is easy to check on any rifled gun using a cleaning rod and a tight fitting patch. Lube the patch with oil or gun cleaner and run it into the barrel so that it takes the rifling and turns with it almost to the other end of the barrel. Mark the top of the rod with a dot at the end of the barrel or a measured distance from it. Pull the rod out allowing it to turn following the rifling until it makes one full turn and measure the distance the dot moved out. Repeat several times to confirm.