These are the notes I posted from an earlier test with various NSA 22 slugs. This was with a stock pre-X impact.
-50 yds, max power, slug-A liner: NSA 19, 21, 23, 27, 28BT, 30, 32BT, and 33 slugs.
The 19, 21, and 23 were clearly the worst groups. The 27 and 33 were very good, with below 1/2" groups. The 30 was excellent at 3/8" group.
For my particular liner, the heavier slugs are better, and in fact the lighter ones can be unstable. When that happens, you actually hear them tumbling, and they're maybe a foot off target. As badly as I want the boat tail slugs to work, they have repeatedly proven (in my liner) to be less accurate than the standard 30gr slug, so I'm sticking with the 30gr for testing power mods. My goal for using slugs is to get the best BC possible, at around 1050 fps. I have the 30gr up to 935 fps so far, so I have some more work to do.
And yes, the "slug" barrel shoots JSB pellets VERY well. I was told there is still a choke, just a very slight one, and the twist rate is the same as the pellet liner. From what I've seen, the slug liner should just be standard, since it shoots both.
And now a word "for" our sponsor. The NSA slugs are amazingly consistent. I've been playing with making my own slugs, and I'm just stunned at the weight consistency of the NSA slugs. I seriously doubt I will ever be able to approach that level of consistency, but it's a fun challenge. The bar is set very high
Cheers,
Rusty