QUESTION

I am looking at the savage Weather warrior rifle OR the varmint, in .243 most likely - maybe 7mm-08. My question - whats the accuracy gain, or advantage of the heavier barrel...this is something I never really understood.... if someone could please explain I would really appreciate it. I want a tack driver is what it amounts to but wondering if the extra 3-4 pounds of a 'varmint' rifle is wort the weight in accuracy.....

Thanks again guys !