Advise needed on Stark Bullets in 6BR

[voldoc02]

I've got an oppurtunity to buy several
Stark 75 gr 6mmRed Mist bullets=
they have the gaping open tips
similar to Berger old MEF's=
I shot some this AM and they show
very good potiential w/ accuracy
about 1/2 to 5/8" 5 shot groups @ 200yds in wind
and cold this Morn.
They also blew 16 oz. water bottles to
smitherines and eggs vaporize or launch
@ 200 and 300 yds. Just looking for
some real world PrarieDog experience before
I load up on 'em, I'd like to use 'em
out of my short barreled 6BR for 400 yds in=
thanks in advance
Doc