We started out shooting .45ACP in a Taurus 1911 when we discovered a .45AR (1917 Revolver), which we both fell in love with.   Our 1917 (.45AR) is a S&W Nightguard 325 with a 2.75" barrel, we added the Crimson Trace grips.   After taking it to the range a couple of times, we decided the full moon clips were a real pain in the rear (at the range), It was about that time I discovered the .45AR brass.   BTW, everyone who has fired our 325 really likes it, its easy to hit with and fun to shoot as long as you use the .45AR brass.   Even though the Night Guard 325 has a large frame, is very light (meaning some recoil) the girls love to shoot it.   I bought a box of .45AR brass from Starline, and started loading it, it worked great and allowed us to really enjoy shooting our 1917.   BTW: We still shoot a lot of .45ACP.

We use the 1917 with moon clips for home protection, since you can reload all 6 shots at once, but when we go the the range, we only use the .45ARs, its a whole lot easier to just load it like a regular revolver.   "Old Blue" is always loaded and handy, with extra moon clips also handy in case someone with ill intent attempts to enter our house.  

The .45AR is a .45ACP with a thiker rimmed base (.006" thicker), so it can be fired in a 1917 revolver without a moon clip.   My understanding is that the U.S. government adopted the .45ACP cartridge in 1911 and chose the Colt .45 automatic as the standard sidearm for all military services (ACP = Automatic Colt Pistol).   But Colt and a lot of the other contractors attempting to build the 1911 had production problems (remember what was going on in the world in 1915 and this was one of the first automatic handguns ever mass produced).   So another manufacturer (I think S&W) chambered a revolver for the new .45ACP cartridge required a Half Moon (or full moon) Clip and was soon in production.   The U.S. government then adopted the 1917 (S&W .45Rim Revolver) as it's alternate sidearm for all services.   BTW: the Peters Company developed the .45AR cartridge for the 1917 revolver in 1920, since there were large quantitiys of 1917 revolvers around (surplus) after WW I.   Our 1917 is a S&W 325 Night Guard with an "N" frame.  

The acutal reloading is the same as loading .45ACP, same dies, same bullets, different shellholder, or shell plate on the Pro2K.   RCBS also has a special case retention bracket for the Pro2000 that is milled out a few thousandths in front of each position for the thicker .45AR bases.   The books usually list a slightly lighter load for the .45AR, but the 1917 was designed to handle .45ACP loads.

Heres "Old Blue" as we call it, loaded, with an extra full moon clip of .45ACP.   This is a S&W 325 Night Guard with a scandium frame and titanium cylinder.   BTW, those are Crimson Trace grips with the laser sight.   The rounds are 185 gn. Gold Dot Hollow Points with a fairly heavy load of Unique.     We also keep a S&W M&P45 loaded with the same .45ACP rounds again to thwart intruders.

Heres our 1917 ("Old Blue") with a moon clip of .45 ACP partially inserted.

You can see how the moon clip raises the .45ACP heads above the rear surface of the cylinder.   Contrast when loaded with .45AR.

The cylinder open showing how the moon clip rests against the back of the cylinder.   Notice we also use StarLine .45 ACP brass.

View of the back of the cylinder when loaded with .45AR.

Heres the 1917 loaded with .45ARs, contrast it when loaded with .45ACP. Note how thick the rims are so the cartridge base is at the same height as .45ACPs with the full moon clip.

Contrast the cases: two .45ACPs on left, two .45ARs on right, note the thicker rim on the .45ARs.

Same for the cartridges, top two are .45AR lower two .45ACP.   All 4 are loaded with Montana Gold 185 gn. hollow points.

Two .45ACP cartridges with a couple of full moon clips.   These we use for home defence, they are loaded with 185 gn. Gold Dot Hollow points and higher loads of propellant (not quite max).   I do have some Hornady "Critical Defence" for carrying.

A DeMooner tool, for loading and unloading moon clips.

Loading a .45ACP into a moon clip.   With the moon clip laying on the center hub, place a cartridge into a notch and squeeze.

A .45ACP loaded into a moon clip.

Heres how to unload a moon clip.   Place the cartridge (usually spent) into one of the holes.

Hold it down with a thumb then twist the clip and the clip comes right off the cartridge.