henpeckedmuch
If I were starting load work-up for a 40 cal rifle, 2400 powder would not be on my list of powders to try. I suggest something bulkier such as IMR 4759 without any sort of wad. The trick is to not dump the powder into the action while loading. Breech seating 1/8 inch ahead of the case mouth seems like a reasonable place to start but you might try seating a bullet to that dept, then push it back out of the chamber and examine how it is engraved by the rifling. A good rule-of-thumb is to seat the bullet so the base band is engraved by the rifling about 1/2 its width.

I am with Crash and Frank on this one. While guys have reported good results with 2400 it's not a common Schuetzen powder. I don't recall ever seeing anybody using it in a formal match. CBA postals  I shot years ago  it was not an often seen cast bullet powder.

Wads are a caution too, only time I use them is with a case full of black, then only to make breech seating possible with a full case.  Generally wad is a crutch to make powders not suitable burn properly and come with chance of ringing. 

Modern action single shot shooters with wildcat short pre charged cases have to use them. Strong actions modern steel barrels and cases too short to double charge or leave much air space between wad and bullet. Traditional Schuetzens rarely use a wad.

BPCS case is full and a very thin wad over the powder protects the bullets base on ignition, or so the story goes. I think they are most usefull when compressing powder, keeps from crushing grains. Since I went to vibrated cases I don't compress anymore and leave the wad out for BP fixed loads. Lets me get a bit more in the case.

4227  or 4759 you can insert most cases without spilling I don't know how long that Sharps case is but 38/55's are only two inches and don't spill if handled properly.  Been years since one of my rifles had to be taken down to clean spilled powder out of the action, then when I was showing a new shooter how B/S worked and he klutzed it.  

Boats