long range bullet for .280

[PrimeTime]

I have great accuracy from the 140 grain Ballistic Tip at around 3080. I am shooting whitetail out to 600 yards. Is this a suitable bullet or should I go heavier?
Also, people have told me (Sierra themselves)
that the Matchkings and A-Max bullets don't have predictable expansion on big game. I am considering one of these bullets but don't want to make a pin hole through a deer.
Any input would be appreciated.

 

[Darryl Cassel]

I have had extremely good success with any of the Sierra MK bullets in all of the longrange calibers I have owned over the years. The 7mms I have owned liked the 168 Gr MKs very much.
Yes, they will expand on deer and elk size game.

Darryl Cassel

 

[Len Backus]

I will be using Hornady's A-Max, 162 grain in 7mm, this year on my Dall sheep hunt and for mule and whitetail and Coues deer. I am getting 1/2 moa (vertical)out to 700 yards with it in my newly remodeled Tikka rifle.

The ballistic coefficient is high at .625 and I feel this must be the key to long range hunting accuracy and minimizing the effect of wind estimation errors. In switching over from last year's 140 grain Ballistic Tip, wind drift should be reduced by about one-fourth.

Does anyone have any experience with this bullet? Will it's expansion perform about like the Matchking?