Muzzle-crown configuration?

[Naphtali]

I have been asked to describe the muzzle-and-crown of a muzzleloading rifle, and what differences there would be between muzzle-and-crown of barrel that loads round balls only and barrel that loads conicals only. I can't do it; I can't furnish photographs showing what was asked either.

I can locate photographs showing pretty much everything on original best-quality and recently made custom-built muzzleloaders - except their muzzle-and-crown.

Anyone who can help me with description and/or photographs, please do.

[James Wilson Everett]

Guys,

Here is a "backwards" answer, the tooling that was used to make barrel crowns on the original guns.  Probably each individual gunsmith had his own tool so barrel crowns certainly did vary much.  Here is an original barrel crown, since the diameter is small, this tool could only be used on bores of 0.5 inch and smaller, so it is probably a percussion era tool.





Here is a modern made tool that I use.  It is copied from an original one that was published in the Journal of Historical Armsmaking Technology.  This one is larger and would be most likely used on bores of around 0.5 - 0.7 inch.



Jim

[Naphtali]

It looks as though it could be a cherry to make an RB mold. If you don't drive deeply enough to do that, I think what I'm seeing is a device that creates a short and shallow concave [edge] at bore's end - that is, a muzzle that won't tear up the patch, or deface a conical's base?

[James Wilson Everett]

Both of these barrel crown tools have a spherical cutting surface, as you observed.  My surmise is that this was done so that any small variation in alignment of the cutter with the muzzle did not effect the muzzle crown or chamfer.  I am sure that you can envision that holding the spherical cutter at a slight angle would not make the muzzle crown off center.  However, if a conical cutter(countersink or counterbore) is used the same misalignment would cause the crown to be off center.  Modern barrel crown tools rely on a bore fitting pilot to keep the cutter aligned properly.  With these originals the exact alignment is a lot less critical.  I believe that the actual chamfer cut using these tools was rather small so there was no functional effect of the cut surface being a sphere.

On an earlier posting I used the top tool as a cutter to make that difficult concave cut for the flintlock flashpan.  The tool worked easily, but the resulting pan cut was ugly.

Jim

[James Wilson Everett]

Guys,

Here is the barrel crown tool that was from the Journal of Historical Armsmaking Technology, Volume II.







The barrel crown I use was copied/adapted from this one in the JHAT Vol II.  However, in a fit of extreme bonehhead I cut the teeth backwards so the tool must be turned anticlockwise!  It still works very well, but widishins.

Jim