I'm new to the 1911 world and have a CS model that won't lock open after the last round is fired. I have the two factory mags and one Colt mag and the results are the same with any of them. With the factory mags the springs are strong enough that with the mag in place it is very difficult to release the slide. Do I need to replace the recoil spring with a strong one or do I get different mags. If it's the recoil spring which make and which one? I know I don't get one for a full size but should it be for a Officer's model size? I really like this gun although that it's not locking open is not really that much trouble I would like the gun to perform as it should. Any and all help is greatly appreciated. Thanks.