If it was called a Pedersoli Sharps then it was probably a Perdersoli Sharps.
The Rolling block [designed by Remington Arms] is loaded by pulling back the hammer and the rotating part of the breech block and inserting the round.
On the other hand, the Sharps has a bloody ENORMOUS hammer on the right-hand side of the action, and a long lever underneath that doubles as the trigger guard.
To cock the piece, the hammer is hauled back to half-cock, and the lever is lowered, dropping the breech-block. the round is pushed into the breech and the lever raised, lifting the breech-block into battery. The hammer is them pulled back to full cock, and fired. To unload, put the hammer on half-cock and lower the lever and start all over again. The extraction is about 1/2 -3/4", BTW.
Both these pieces have hammers, the Sharps as big as any percussion musket.
The only 45-70 firearm that is vaguely as you describe the one you said you shot is the Ruger No1 - THAT has an internal hammer, and what you might call a small lever on the trigger guard. Do you mean that the hammer was visible, but behind the breech block? If so, then you have shot a Remington Rolling block, not a Sharps. Both are made in replica form by Pedersoli, and loading for them is a breeze.
Best with real BP though, rather than Pyrodex RS or C.
Have a look at these, and THEN tell us what you shot....right now, as right now I'm as confused as you are ...
Remington rolling block - http://bubbler.files.wordpress.com/2008/03/overview.jpg
Sharps - http://www.cherrys.com/pedpics/S771b.jpg
Ruger #1 - http://www.leveractions.com/images/No1Alaskan.jpg [take off the scope of course]
tac