How hard is it to break into ML work without a Master's degree? [D]

I'm currently a software engineer (mostly mobile/iOS development) and have recently started learning machine learning because I genuinely find it interesting, especially the math behind it. I have a fairly strong math background and am comfortable with calculus, probability, and math in general. Right now I'm learning through a combination of Andrew Ng's ML course and Stanford CS229. My plan is to build some projects once I have a stronger foundation. What attracts me to ML is the mathematics behind it. My