The company kindly gave me few US-S slugs to test at high speeds.
I had helped him test another slug a while back.
He sent me some each of the US-S 570 gr, 700 gr, 970 gr.
I tested the 570 gr so far and in 3.5" plastic case in the 1887
smoothbore 35" barrel and in the NEF rifled 36" barrel at
1900 fps. I got that with 130gr of RE17 with one BPGS
seal under the sabot on the slug. The bottom of the sabot seal
is exactly like a BPGS, so a BPGS added gives double sealing.
Both smooth and rifled gave 3 shot 3" group each at 50 yds with
peep sights and bad eyes. This slug does as good as advertized
in smooth barrels, and smooth accuracy is as good as rifled.
My smooth barrel is tight, measuring 723" at muzzle.
These should be a great deer and hog slug. Folks need to
ask their dealers to work to import these for them
to have what seems a good slug to reload...

On another note we may have found a guy who is gearing up
to make 10 ga rifled barrels. I'll know later this winter
If so I will put one on a bolt action and use the 4.1" long
10GA FH case I made or get some like it from RMC..Ed