I built a gun. Answered
Over the summer, I designed and built an extremely simple single-shot .22 pistol. Below is a video showing all of the parts and the first shots fired. I did this as a design exercise and to see how hard it would be to build a reliable firearm, going from idea to 3D model to working prototype in about three weeks. So far I've fired over 200 rounds with 0 malfunctions, however some parts still need to be heat treated and I need to apply a finish and maybe add some sights. When it's completely finished, I'll port my blog posts into an instructable.