They were round nose. Until the advent of repeating rifles in .45-70 came along (Winchester Hotchkis, Remington-Keene, Winchester M1886, Marlin M1881, etc.) there was no need for a flat meplat. Overall length for the government 500 grain and 405 grain loads was about 2.55". There was no need to limit the overall length of the bullets in single shot rifles since most of the bullets had the portion beyond the mouth of the cartridge case about the diameter of the bore rather than the grooves. BTW, don't let the term "cylindro-conoidal" found in original specs confuse you. This simply refers to a round-nose bullet with a cylindrical body. The use of pointed bullets in big BP cartridges like the .45-70 is pretty recent. While they may give a slight edge in ballistic coefficient, the longer length for the weight requires some faster twist rifling than was common in the original rifles. I have seen Winchester HiWalls with a 1-in-19" twist, which will handle bullet that are fairly heavy and/or with sharp points, but generally the twists run 1-22, especially in military rifles and carbines.