I am wanting to begin working up a hunting load for my Shiloh Sharps 50-90. I am not a beginner in reloading but have not done much with BP cartridge reloading. I am well aware that for every aspect or step in the loading process there are multiple choices depending on the particular gun, load and loading method. With that said, I am only looking for some basic (starting) advice. So here is what I intend to initially start with. Please feel free to chime in.

Swiss 1.5 powder
large rifle mag primer
550 grain 20-1 grease grove bullet ( I will verify the bore diameter before sizing my bullets and size to .002" above the bore size )
SPG bullet lube
I will use a 24" drop tube
I will use an over the powder wad, which initially will probably be  a vegetable based paper of around .060" thick. 
I have read that Swiss does not like an excessive amount of compression so I intend to adjust my powder charge to allow for about .060" powder compression when the bullet is seated correctly. I have also heard that sometimes with full bore loads, in my case would be 90 grains, the accuracy can suffer caused by to high of a velocity causing some stripping of soft lead bullets. SO, I am open to any suggestions to save some time getting started working up a decent load for hunting. This will not be a competition rifle. I am only looking for a good hunting load. Once I get a good base line I intend work on what it might take to tighten things up. Hopefully this makes since. Thanks

   

Not sure if you have a compression die but it is not a good idea to compress the wad and powder with the bullet.  If you do a chamber cast you can see how much freebore you have and what that diameter is.  I like a duplex load of 10% smokeless powder such as RE-7 or 5744 to reduce fouling for hunting.  You might also want to try a lighter bullet such as 450 grains.  I have a 50-70 Rolling Block and normally shoot 512 grain Accurate Mould bullets but it lets you know you pulled the trigger so a 550 grain bullet might kill at both ends!  After I did my chamber cast I had Accurate Moulds make me bullets of 450 and 512 grains at the size I wanted so that I don't resize the bullet at all and pan lube them. The one good thing about the 50's is that the bullets stand up and never tip over in the tray while pan lubing!  They also kill!  I sometimes wish that I had a 50-90 and then I shoot the 50-70 and am more than satisfied! My rifle hates 30:1 and 25:1 alloy but does well with 20:1 and 16:1.  I killed a buffalo with the 512 gr 16:1 and recovered both bullets and the front flattened out to maybe 60 caliber and they still weigh over 500 grains.  Have fun working up loads and don't be afraid to wear a strap on recoil pad on your shoulder.  Tom

I'd say forget about the drop tube  - you'll be able to get more than enough powder in that case without it.  And Fg might be better suited, but 1 1/2Fg will do just fine.
And that bullet stripping because of the velocity with a full load, it won't happen.

JHM, your mama never raised no fool!  Tom. 

A huge thank you to everyone. Considering all of your suggestions, I believe I will start with a duplex load, probably with 8 grains of 4227 since I already have some. A .060" veg. over the powder wad, Swiss 1.5 at around 80 grains depending on the amount of compression, and initially compress it .050". I intend to make my own adjustable compression die on my lathe, so after I get that finished I will give this a try and let you know how it all turns out. Thanks again.