I have not shot any AVS slugs in either of my 25s. But JSB Knockouts expanded to about 3/8 diameter at 25 yards when they were launched at about 800 fps by my Avenger. My P35 is only tuned to about 35 fpe so heavier slugs do not expand but 28 grain H&N Slug HPs expand a little at 25 yards. I test penetration in wet paper. The P35 launches the 28s at about 700 fps.
I am somewhat intrigued by slugs but I have not shot any animals with a slug and may not. Their penetration is inversely proportional to their expansion. If they expand, penetration is much, much less. The H&N 28s penetrated only about 2 inches in wet paper, about like domed pellets penetrate from my little Prod. Domed pellets penetrate about twice that far from that gun. I had similar experience with the testing of knockouts from my Avenger. I drop squirrels well with simple domed pellets so I don't really need expansion. The only thing the terminal performance would do for me is limit the remaining velocity after pass through. But if I miss, the slug will carry more velocity further. I also wonder if I don't need to understand better their penetration/expansion versus velocity.
But to come back to the topic, I think you have enough velocity to see expansion with either JSB Knockouts or H&N Slug HPs. I don't know if the AVS did not expand because you shot into water or because they are just tougher, slower to expand, slugs. I looked for my notes on shooting into water but did not find them. Seems like I did see expansion on the JSBs but I'm not sure.
