Curtis, a good BP load is one your rifle likes. You could start by dropping the bullet in the chamber and measuring the distance from the end of the barrel to the base of the bullet. Transfer that distance to the case and see where the base of the bullet ends up. Everything below this is the space available for wad and powder. The two basic ways to get the powder in the case are by just dumping it in or using a drop tube of a couple of feet length. The drop tube will yield more powder in the same space. This plus the wad is your base charge with no compression. Some powders, like Swiss, are fine with no compression. Some, like Goex seem to like compression up to maybe even 1/4 inch. To add more powder you must use compression but not with the bullet - it will be deformed. Use a compression die. Do not crimp the bullet. Try large pistol primers. Somewhere in all this you will find what the rifle likes. Its more like alchemy than science.

What Mike says is true

When you say it's a chore to seat bullets with 80gr of powder, what exactly do you mean?  With a compression die you can control seating depth very easily.  If you don't have one, it's an excellent thing to buy.

BTW, Is your rifle a C. Sharps, or a Shiloh?  The Long Range Express is a Shiloh model.

Chris.

Everything I have shot through my gun so far has been phenomenal. I had some 5744 loads with 405's that shot one ragged hole with the sights. I would just prefer to stick with BP since that was what were originally for.

29aholic, it sounds like you have never loaded bp in cartridges before, and if I am wrong I apologize right up front. One thing you should have is a compression die to compress the powder. Next is you need to determine how much powder it takes to fill your case to the bottom of the bullet. Do this by loading a dummy round to where you want the bullet to be and then measure the OAL of the round and subtract the length of the case and the length of the bullet, the resulting number is how deep your powder charge should be from the case mouth. That is how far you want your powder compression plug to enter your case. 
Start your load development by filling your case with powder to that depth, seat a wad and your bullet. Then work up your load by 2 grain increments, nothing else changes just the amount of powder you are using. Your rifle will tell you when  you hit the magic volume.
I hope this helps you out some. 
Sam

Curtis: A good reading primer: Introduction to BPCR Reloading
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Joe, when Curtis posts his rifle pictures - got another good link written by Dick Trenk   

Sorry guys, here is the requested pic. I looked at it last night and it just says Old Reliable on it, but I believe it is an early Heavy Hartford. That's my daughter in the pic. She swearing at me under her breath "Take the f**king picture already, this b***h is heavy!"
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