Don't get frustrared by keyholes. Pay strict attention to bullet weights and double check seating depth. If you are only shooting from one rifle I would NECK SIZE ONLY to avoid the hassles of proper shoulder sizing. I found this a real issue when I was F.L. sizing cases. When it comes to powders, I would stick to the manuals. Varget has given some nice results for me. As far as the components that you mention, I found the 4895 a tad on the slow burn side. I was also playing with light bullets too. I recall 36g , perhaps why I had issues with keyholes! That's all I've got as far as experience with that cartridge. Remember, there's a bunch O'powder igniting behind a wee bullet so I'd be wary of pushing past max-rated loads. Cheers.