Reversing the cartridge trap would have placed the sing swivel too far forward with this design of trap. If I ever do another one I will certainly place it to the rear but I haven't figured out how to keep the sling swivel further back yet. Another one of my points to remember....I stopped drilling to double check the depth of the front hole and couldn't complete the hole for a cartridges OAL. It would have gone through the top of the stock. The front hole is for the snap cap or firearms license (which has to be carried with a firearm in Canada). That's my story and the owners good with it!