I have a heavily modified/heavily used KWA G18C that I have had for a couple years now. It has well over 30k rounds through it. The problem I have been having lately is that it will not properly cycle the slide if I don't push the magazine up into the mag well. I am starting to lean towards the slide being the culprit just due to that age and usage of the gun, and if I gently push down on the slide there is substantially less play (up and down). If anyone has any tips or tricks that may help it would be greatly appreciated. Also, I'm not sure if it makes any difference, but I have a Guarder steel magazine catch installed, so I'm not sure if that could be contributing to my problem too.