I am going to load up a box with Longshot using the load supplied by
J.A. Early and from Precision Reloading in an earlier post.(Thanks).
Cheddite 2 1/2", W209, 18 gr Longshot, SG 16 wad, 1 oz, 1200fps@7270.
I will use the same formula but go to 7/8 oz and give them a try/comparison.
If I knew someone who wanted the Longshot, I would just sell it to them as I found/bought 2 lbs of PB yesterday

I recent experiment of mine using a slow powder for light loads had an unexpected result. I believe that the load I used wasn't creating enough pressure to seal the shell walls to the chamber walls. It was suggested by another member that I use a faster powder, which I intend to do when I am able to find some, but until then I'm going to raise the shot wieght a little at a time and observe the results.