Ummm, how so? The Colt 1917 was barely more than a M 1909 with a .45 ACP capable cylinder. When the US entered WWI and found itself short of M1911s, it asked both Colt and S&W to provide .45 ACP capable revolvers to supplement the shortage and they both used existing models to quickly accomplish that; Pershing had wanted each soldier to have a handgun. I'm pretty sure that they didn't alter any rifling to match ballistics with jacketed ACP ammunition. If so, I'd like to see those statistics.
The expedient had already been found in the shape of the Model 1873 SAA revolver when the .38 "long" proved ineffective against Filipino rebels, the Moros in particular. The military took a lesson from that and decided that in the future that the larger caliber should be a standard sidearm and the M-1909 was the first contracted issue of a "modernized" (i.e. doubel action) handgun, that is double action like the .38s, but with the .45 caliber, similar to the .45 Long Colt (it was supposed to have a wider rim for better extraction). The trials for the auto had already begun by then (as early even as the 1890s) and the 1909 was really more like an interim design until a satisfactory semi-automatic design could be approved.
The Colt 1917s were not parkerized, but rather had a somewhat rough polished blue, the S&W blue being much better polished.
I highly recommend a S&W 1917. Although I like the Colts fine, I think the 1917 is the best revolver S&W ever made for the military, and mabye the best revolver the military ever issued. I think you'd find better use for the ACP, after all, you gotta' love those moonclips, half or full!