Why would you want to build a .45 GAP 1911?
Like I said, just want to do some experimentation. I've got "wildcattin'" in my blood!
It would be interesting how it would perform in a bullseye format type pistol. Since your are using reduced loads anyway, why not? Just like accuracy in a rifle, the fuller the case, normally the more accurate the load will be.
That's the reason behind this foolish thought. An expensive experiment.