Just a quick note for those that might be interested:The highest velocity I have attained with the .45acp is: (185 grn. xtp bullet, speer acp cases, cci magnum primers, alliant powder)=1778 f.p.s./
1299 f.p.m.e. using a 5" 1911

4" xd only got 1709 f.p.s./1200 f.p.m.e.

Both guns had been modified. It is just like building a hot rod. Lots of components being changed to get more horsepower. Lots of reloading tricks for the ammo too. Good shooting to you all.