Just wondering...how big of a gap is too BIG?
Colt specs were .001" to .008", anything beyond .008" failed factory QC check
Remington barrel/cylinder seem to stay tight forever. Mine is 20 years old and still tight, with decades of full cylinder loads put through it- with a Remington, the pin, pin hole in the recoil shield, and pin hole in the cylinder all start to wear together. You can tell when a Remmie needs some work, when cocked the cylinder doesn't just turn, it goes upward in the back- starts getting more pin/cylinder play.
the nice thing about a Remmie is, you can buy a new cylinder and pin, and presto you're back to new- if need be, you can also bush the recoil shield to tighten up where the pin goes in as well- they are just a far superior design for long term heavy shooting, and much easier to repair
on the other hand, shoot a cast frame open top long enough, with full power loads, you're going to have .010" to .020" play pretty quick, most times. I had ONE Navy Arms 1860 that held up really well with full power 39 grain loads. The Walker loosened up rather quickly to about .020" with 60 grain loads.
brass frames, forgettaboutit...loose in no time, with one cylinder practically
it all depends on how hard the wedge, arbor slot, and barrel slot area is with a Colt. The softer it is, the quicker it's going to shoot loose, and the bigger the gap is going to get- requiring a wider and wider wedge as time goes on, to put it back into spec
that's why metallurgy is so critical with an open top, the wedge interface is highly stressed due to the limitations/nature of the design
I could live with .020"- beyond that, I'd be looking to tighten it up a bit