At what velocity do you normally shoot them and what’s a common distance? I use Varmint Knocker slugs more often than the NSA’s anymore because my gun loves them and I don’t have to changed tunes between the VK slugs and JSB MKII pellets. I have absolutely destroyed stuff with the 33.5gr. slugs at between 940-990fps though. A big part of expansion, as I’m sure you know, is the velocity, the energy upon impact and what part of the animal the slug hits.
I’ve heard these complaints about them not expanding before but have never really experienced the lack of expansion myself. What’s interesting is that there have been plenty of videos posted on line, showing the expansion of these slugs. Some video’s show them expanding like crazy in water, others shot in water, no expansion at all. Same thing in ballistic gelatin, clay and meat. It is a little perplexing and hard to explain after watching videos that show exact opposite results.
If you really want expansion and complete devastation, try the Varmint Knocker 32.8 or 34 grin slugs. They’re made of much softer lead and have a larger hollow point. My son was practicing with the VK slugs one day, shooting our 135yd. gong when a digger squirrel ran under the gong. My son asked if he could shoot it, I said yes and even at that distance, it was blown completely in two pieces...Other than a little bit of fur and skin. That shot hit the squirrel right in the abdomen and made contact with no large bones, maybe just a rib or two. The damage was done from the expansion and hydrostatic shock and it was gnarly!!!
Have a good Sunday afternoon!
Stoti
Below are a sampling of just a few of the slugs I tested over the past couple years. There are so many variations in lead/antimony content and the size and shape of the hollow point that contribute to expansion.