Thor slugs are manufactured in South Africa and they carry the range 177, 217, 25, 30, 35, 45 & 50 cal. Their slugs are very similar to FX Hybrid slugs with a deep rear section, which creates a good air seal with the barrel.
Left is a JSB Beast 16 gr pellet then 15 gr, 17 gr @ 19 gr, they manufacture a 13 gr as well but unfortunately I didn’t have a sample to add to the line up.
Above are the 15gr slugs which I shot into my silicone baffle box at 965 fps, the expansion is outstanding. I have also field tested the 15 gr on pigeons and they have outstanding transfer of energy, I would say better than any non expanding 22 cal Pellet I have shot.
The 19gr really puts the hammer down but you have to push them hard to 950 fps . They have great accuracy at 22 m shooting paper and I have shot pigeons out to 90m with them.
My 177 slug gun is a SPA P12 fitted with a Weihrauch barrel 605 mm long and I think it has a 1:17.7 twist. My transfer port was 3.5 mm Dia but I have upgraded it to 5 mm Dia which makes loading tricky but I have a technique.
With the larger transfer port the hammer spring is now only set at 2 3/4 Turns to push the 19 grs at 950 fps.
Thor slugs perform very well and are reasonably priced not every day you can kill two birds with one stone.
Time will tell how they group at 50 and 100 m