No offense, but sounds like shooter to me. The other rifles you listed are not know for horsepower. Easy shooters.

A 7mm Mag. is a kicker. It can take a lot to get used to and usually the shooter (myself included) can be seemingly unexplicably inaccurate for a while. When I got really good with my .30-06, I thought,well, I can shoot anything. Wrong. I got a .300 Win Mag. a while ago and it's a whole different ball game.

I tried really hard to blame the rifle, but I found an easy check. Vise the gun at the range. If they don't have one, borrow one, or buy one. They're usually not too expensive. After vising the gun, and thus mostly eliminating me from the process, I was surprised to see really tight groups. To my amazement, once I realized I was the problem, I started to shoot better almost immediatly. I'm still not as good with it as my other rifles, but I'm getting better. Keep at it.

By the way, if it turns out that the rifle is loose after putting it in a vise, then it's very possible that the barrel is too new (as mentioned before). Give it 50 to 100 rounds, then try again. If it's still f'd up, take it to a gunsmith and let him evaluate it. Other than that is beyond my espertise.