25 caliber 26.8 gr. NSA probably traveling about 880 fps when it hit the squirrel. Shot was through shoulder but a bit too high, missing the boiler room. No worries. Wound channel was HUGE and obliterated spine. Squirrel fell in place.
If the NSA's don't do anything else they EXPAND. The blunt nose only make them more devastating, shot a squirrel @20y with .30cal 43gr over 900fps, no pass thru. I might experiment with using fillers in some NSA slugs to maybe reduced expansion and help penetration, thinking of using wood glue to fill the cavity.