I purchased a 56-50 Armi from GA dealer (700 including shipping and transfer, as new, original owner could not bring himself to purchase ammo, wow) and am awaiting arrival (you know the dance, shipper wants FFL from transfer agent who wants shiipers FFL first, and I don't have either). 

I have been reloading and shooting a 50-70 for 30 years (repro Sharps 59 conversion) using the 440 gr lyman bullet sized to 509.  It is very accurate in the faux Sharps at any reasonable range.  This bullet is a flat point but not a large flat by any means.

Has anyone used this bullet in the 56-50 and does it load to short enough length to function?  Using smokeless powder only here.  Also hope to find Trailboss loads for this weight.  Thanks in advance, Captn Jack.