I recently picked up a .45 ACP and made the same discovery quite a few other people have made. It is difficult to shoot in DA mode with normal sized hands. This two-part video series shows exactly what the problem is, and how to fix it.
Part 1 shows a range session with the as-is model 325, and Part 2 also shows a range session with the improved revolver.
Part 1 - The problem
Part 2 - The solution