Disclaimer: If you are here then I will assume you understand the 1911, its design and function. If not I would recommend you learn about the weapon and study its blueprints and watch a few videos on assembly prior to starting. I would also assume that you understand using precision measuring tools along with metal cutting tools, file, drill’s and simple hand tools. Most new builders lacking experience, and working on a mill will struggle using the mill fixture. The PRC is better tool for the beginner builder with huge success rate. It’s still a tool and people do fail with it as well. Know your own limitations do some research and get familiar with the work prior to diving right in and throwing chips. The biggest mistake I see is not measuring. It’s not like a Glock build ware you just trust some jig and cut out some plastic. You are responsible for knowing and following all of your local and federal laws with any projects you may build. 1911’s are for life so build a good one.