FWIW I use the 87 gr Hot Core in my 20in 1899 TD. I didn't realize how much I prefer accuracy to bullet weight until I did.
It is a 1.5-2.5 inch gun with 100 grainers but sub one inch with the 87 gr.
Bullet holds together really well too.
As to the Speers in general I like the flat base Hot Core bullets though I have used more 165's than 150's.
The BT's aren't Hot Core as most know and they do not hold together nearley as well.
