huntinfool41
Here is what I would suggest and what I would do your situation...
Do not change to musket caps
Do not change to T7 pellets - If you have been using RS (120 grains will do the job... -stay with the know.. and the #11 Mag (make sure yours are mag caps or even better if you could come up with some Dynamint Nobel 1075+ #11 caps stay with that. (sportsman warehouse).
At this late date if you have confidence to shoot the 300 Precision in the right place - stay with it - it will do the job if you get it tucked in behind the shoulder or even in the brisket with a head on shot. Even if you get a solid hit on the shoulder bone it will get into the chest cavity.
If there were more time I would send you some 460 Bull Shops ( I livein Moscow/Pullman areaand I have a contact in the Tri Cites area that could get you some -
but that would require re-zero and testing - same thing if you went to a 405 Power Belt... Stay with what you have - hopefully keep your shot under a 100 yards - take your time and make a good shot and you will have your elk..
Best of luck to you....
mike