This document is the creation and report of investigating how gamma photons penetrate metal with the goal of seeing how much of a metal is required to stop gamma photons completely. It outlines various types of metal with a primary focus on lead since that is what is used in real life circumstances and all data is obtained from software. This associates with the radiation part of year 12 physics and can be used as a teaching aid when discussing how not all metal are equal and that density is an important property. As with it being a practical report it goes over the sources of error and that a simulation does not always reflect real world scenarios. This report received an A+ due to the extent of research done which far exceeded what was expected within a 1.5 week time frame.