What about a 90 grain Ballistic Tip?
Should be more than enough for your intended purposes.
Or the Hornady 87 grain BTHP if still available.
Hell of a bullet that you dont hear much about.
I agree with 10gauge....
would also consider 75 grain HP, Sierra or Speer...
70 grain TNT or 70 Varmageddon...
or good old 80 grain Winchester, or Sierra 80 grain and 85 grain SP....
87 grain SP Hornady also.....
Plenty of good choices out there...
the 87 V Max is a good one.. the 75s I can't get to group well enough in anything I shoot that uses a 6mm bullet...
100 Grain SP from Hornady or Sierra are good bullets also...
addendum: heck come to think about it... the short list would be BAD bullets in 6 mm...
Lotta good bullets on the market that just plain work on a lot of stuff..
