What is this?

[Pulp]

Obviously a rim fire. Next to a .45 Colt for scale. In an old tin of cartridges I’ve collected through the years.

 

[HFS]

Totally guessing here.
Could it be the 10.4 x something millimeter for the Swiss Vertelli (spelling?).
I believe that was a bottleneck rimfire round.

 

[Cowbaby]

.41 Swiss Rimfire. Some old Peabody Single Shot rifles used them. Sure wish I had one of those to play around with.

Box sold here with your LB headstamp

https://www.icollector.com/41-Swiss-Rimfire_i40073182[/URL]

The other poster is probably not wrong either.

 

[Pulp]

Thanks for the replies.