Mike, I would highly recommend not using ballistic tips for hunting. Go with the AB or E-tip. Or maybe try the Barnes TTSX. As for the VLD's you will get mixed opinions on them, but a lot of guys including me will not rcommend them for less than 500-600 yd shots, outside that they are a great bullet.
Also, I may be wrong but I doubt your problem is the bullet. But it sure doesn't hurt to experiment.
How long do you wait between shots? Do you give the barrel a chance to cool after each shot?
Is your barrel free floated?
You might try putting some card stock wedges between the barrel and stock where it joins the reciever. Sometimes a preassure point here will stabalize a barrel. If it works a more permanent soloution would be to put a small amount of bedding material in there. Check the threads, you'll find some info on this.
Hope it works out and let us know what you find out.