In another thread Zulch asked to see pics of my Open Top. Hope you weren't expecting to see an actual Colt antique, Zulch. Nothing special about mine, a Uberti made replica.
The 5.5" barrel was added after purchasing it with a 7.5". I just have grown to like the "artillery" length barrels on single action revolvers. No problem with fitting so I can easily put the longer barrel on if ever I or my heirs want to.
The pic of the cylinder close-up shows a fresh, unfired, un-crimped, un-expanded Srarline 44 Special case. It will not fully seat showing the chamber is short. This problem is only similar to Zulch's ammo chambering failure in the other mentioned thread, but with a different cause. For my own gun, I load 44 Colt and 44 Russian cases.