Hi, I'm Mark Serbu, lifelong gun nut, degreed mechanical engineer, gun designer, founder and owner and president of Serbu Firearms, Inc. I'm also a pretty decent selftaught TIG welder, machinist, CNC programmer and assembly guy. I'm trying to teach the basic principles of firearm design and engineering (which apply to ALL product design and engineering), including mechanisms, materials, heat treat, stresses, math, etc. Thanks for stopping by!