[bigred76]

The only way to do it with your current marker body would be to get an ACS bolt that's rear cocking, a screw the same thread as the one in the back of the bolt that holds on the cocking part, and a nut. Take off the rear cocking portion, thread the nut onto the new screw a little ways, and thread the screw into the rear of the bolt. When it's the right length for you, snug the nut up to the back of the bolt.