Thank you all for the replies.
I have taken a couple of deer and a pig with my .58 flint and all with round ball.
The last was a nice doe at around 130yds. Broadside double lung shot that went through. Absolutely no blood for the first 40yards (in 3" of fresh snow).
I wondered after that, if I had been carrying my.50 ball rifle , if I could have had the same results. If the shot had gone through the shoulder would things had been different, (unless I was shooting slugs) especially with the smaller rifle.
I have never shot anything with a conical, but I agree with clodbuster and sabotloader that they have their spot, especially in the area of trajectory and penetration. I tooled up an extra barrel for my underhammer this year in .50 with a fast twist, just so I could take the longer shots. With the .58 I got the results I was looking for anyway.
As with everything else, I know that placement and design are important. Those TC slugs shoot great but they have to act like a solid. Put it on the point of the shoulder and it's going through. I don't know where RCL shot the doe, but I'm sure that the HP had something to do with the results.
Will's shot was something else and looking at everyone else's results, if it was a regular chest shot it would have gone right through regardless of range (within reason) It only stopped because it flattened out. Nice shot.
The project I am working on is OT but the science is the same as ML stuff. I cut a few molds (410 and 510gr) for my rifled 20ga to try to boost performance without going to sabots. The twist was too great and the only way they would shoot consistently was at low velocities which would play heck with trajectory.
At this point I'm looking at a slow twist 20 bore barrel to make a centerfire ball gun. The .62 ball at 1500 should shoot fairly flat and will give me fewer headaches than the conicals. I still have the conical molds to play with anyway.
If anyone has any advice on this project (including a good barrel maker, I haven't made the decision yet) it would be appreciated.
I can move the topic if I have to.
Thank you everyone, and if you have any other stories to post, please do so, they are a great read.
Cheers and Happy New Year
Tom