Goody, SASS #26190

I did send an E-mail to Gary and am awaiting a response. The 44 Uberti Remington 1858 conversion uses 45 Colt cartridges. Is the bore of the 1875 Remington in 44 Rem. the same bore dimensions as the 1858? IF SO, could a 44 Remington 1875 Cylinder be re-chambered for the 45 Colt cartridge? I have 150 smokeless 44 Rem cartridges coming from CAD , a company specializing in obsolete cartridges. They use 4 gr of Bullseye instead of BP as a choice I can order lead from them but can't find dies or instructions on a heeled reloading setup. It would be MUCH easier if the cylinder were re-chambered, Where would I find info on the barrel dimensions, The cylinder dimensions are such that this re-chambering is probably feasible. Any help appreciated. Dirty Doc