The Springfield 1911 can be a good building block providing you purchase one that has a frame that the serial # begins with the letters NM. those are forged steel frame and slides
the rest are investment cast, not a good choice. All of SA 1911 are full of MIM parts, with the exception of the professional model. I know many of you are going to that MIM parts have improved to the point to where it is not an issue anymore. I have been building full house custom 1911s for over 40 yrs and i do know what im talking about, MIMis not and never will
be up to snuff compared to metal like tool steel or forged steel. if you wish to believe that then thats your call, but MIM lacks the structure of quality steel. MIM is just metal particles
bonded togather by in laymans terms glue or bonding agents which ever you want to call it.
In my maany years of building 1911s i hve seen these parts fail too many times