I’ve seen what Barnes 250g Expanders from 2-300 yds when started at 2200 fps by 3 50g pellets. In my experience, they’ll expand to about 225yds, but after that, I think you’d have to hit shoulders to do any more than punch a 50 caliber hole through a deer. These deer and antelope were shot with Knight muzzle loaders using 209 primers.
I’ve shot other sabot bullet combinations but never found a combo that shot as well (1” to 11/4” groups).
I played around with the 300g Expanders and while they shot as well, I doubt they would expand any further out.
I picked up the tipped version of these bullets and will test this summer. I suspect the streamlined shape will shoot flatter but I’m not sure they’ll open faster than the standard version which I can only describe as flying ashtrays.
Those are a 175-200 yard bullet. You have to start with a 45 like the powerbelt ELR and other bullets that are sized to bore dimensions for the kind of accuracy needed at 300-400 yards.
