Well yes I've seen that too from the 50, the point here, in the long run the bigger rounds have not impressed me with the same shot placement.
There is no secret to this, regardless of what some folks think, especially when doing samples of only a handful.
Took us a few years IE 2 IIRC, to see the speed freak 257 wtby death ray produce a run of much more than 30 steps max... but it finally happened. And has happened since.
OTOH my opinion says if you wanted to run a frangible bullet as fast as you could, over 3000, over 3500 preferably, one that would at least make it through to the ribs on the off side, then that bullet, while it will damage way to much for my taste will likely produce the faster kills over all in the long run of averages.
Of course why that much matters is up to the individual and I"m good with that.
