Ken,
That 3 shot cluster is "usual" accuracy based on my experience with the .460. The load also usually shoots tighter than that when the load is 115gn of either H 4350, IMR 4350 or 760 but the older 500gn Hornady RNSP I used was not a good penetrator at the 2500fps these loads produce. Hopefully the newer Hornady's you are using are better.
Somewhere in my color slides, I have pics of 5 shot groups shooting .6 MOA
I recommend you also try some 400gn Woodleigh Spire Points as they shoot very well.
John
