I am re-barreling my 7mmRemMag and would like some advise on the rate of twist.
I ONLY use 160gr bullets, so I was wondering what is the optimal twist for this.
I am going with a #4 contour barrel, which will replace the #3 Winchester factory barrel in order to shift the point of balance foreward, as well as cut down on muzzle jump. Do you fellas think that the #4 will make that much of a difference?? Thanks!

Well, point one on the #4 contour is WHO's #4 is it? What maker? All #4s are not identical.

The short answer is Yes. You will have a little difference. I have a 24" #4 on my 7mag and wouldn't change a thing.

1-9" or 1-9.25" twist will be perfect.

Interestingly enough, there are some barrel makers that have a 3 groove 7mm button that seems to be a sweet blend for the 280 and 7mag and 160 grain bullets.

When Greg Richards still owned "Broughton-Richards" barrels, the 3 groove bore was 1 of his best. I've heard similar stories from other makers. Must be something to it.