a new mag runs about $30 so new o-rings when the ones u have totally crap out is an excellent idea! another excelent idea, is to keep some gas in the mags at all times. like a half a second's fill. this keeps the o-rings plump and moist (theres a little lube mixed in with the green gas). this will significantly prolong the life of the o-rings. of course, to put off buying o-rings even longer, you can do what i did, and turn the existing ones inside out when they start leaking