Ahhh cough , cough.
This could be a good topic that could be learned from , so lets turn it that way , shall we .
Now I don’t know about others here but I have found little documentation to support scopes like the Malcolm being in vogue.,. Really ever when it came to muzzleloading rifles .
Now that’s not to say they were not used . It just does not seem to be anywhere near the prevalence of todays scoped rifles .
Now where you do see them is in long range target shooting .
BUT again ,,,BUT,,,, when you get down to reading about some of those shoots , they also in some cases forbid the use of scopes .
Another thing I have noticed is sometimes what people assume to be a scope ,,, isn’t a scope but a Tube sight . IE no optics .
I had the privilege of inspecting an original Enfield that was mounted with a Malcolm back in the mid 1980s . This was a rifle in the national Infantry museum .
The scope had very little magnification and its field of view was very small . Literally one would have to search for the target .. My small 2x scope on my 22 has fare better optics and field of view .
It also appeared to me to be very week and easily knocked out of alignment .
The armor there told me that they also had a very bad habit of fogging up and in times of high humidity were about useless.
I was also told there were to different types of alignments .
There were early cross hairs and also posts . These were from what I was told , very easily knocked out of alignment
The reproductions today , are what RollingB stated . Basically nothing more then long brass tubes with modern components inside .
So again did they exsist , ya they did . Were they as common as some folks want them to be ??
No not that I have found .
In vogue ?? Sorry , that doesn’t seem to be the case if that comparison is even meant to be a comparable small% of what we see today
I would agree that they existed far more common on some of the early cartridge rifles but even then I have not found them to be very wide spread .
What I would recommend is posting this question in the long range shooting forum and see what hits you get .
A couple of those guys in there are very knowledgeable about the history of that sport
IMO your far more likly though to find suporting documentation for the use of tall post , Creedmoore or verner style peeps then the malcolm scope when it comes to muzzleloaders