The primary problem with shooting shorter case length cartrigdes such as the .44 Special in a 44 mag is the bullet is not seated firmly into the Throat/rifling. Accuracy suffers in any instance where this occurs. By accuracy I mean tight groups at a distance. I don't believe you will find anyone shooting a 454 or 45 long colt exalting the accuracy of this setup fired from a 460 S&W chamber. HOWEVER, accuracy is sufficient for popping turtles, cans, cactus, and small game. 4/10,000ths is INSIGNIFICANT. The case expands more than this during the firing process. The 45 auto rim has been tested and works just fine in a .460 chamber, however I cannot direct you to any technical writings. Pick any 45acp cartridge (.452) either metallic or lead and start reloading into your auto rim cases. (Cheap and FUN!!!) Your pocket will hold bunches of auto rims!
Incidentally, the auto rim case is much safer to shoot than significantly reduced power charges in a .460 case!!! If held in a manner where the powder is tilted away from the primer, it is possible for not all the powder to burn resulting in a stuck bullet in the barrel. The next bullet fired will be the disastrous one.