I got the H&N slug combo pack in both .217 and .218. I’ve shot the .217’s at 17.5 yards and 25 yards with my 22 caliber Dreamline classic. I got the gun on August 26, and have not removed the shroud so I’m assuming it’s a Smooth Twist X liner (as engraved on the receiver). It has shot really small groups with the 23 grain and 25 grain slugs (1/4” and less). They also mushroom out to flat lead discs. The heavier the slugs, the less they mushroom. I have not chronographed the slugs, but the gun was chronographed with Hades pellets at 892 FPS.
The regulator is set at 100 bar, so I think there is room to push the velocities higher, and I may do so when I’m not quite so busy. Before I do that I will shoot the slugs out to at least 50 yards. I like the idea of the slugs with their higher BC and better wind drift, but the Hades shoot really well and the slugs need to be similarly accurate before I’ll switch.