The Rice barrels are smoother inside as well. Rice and Getz are bored, reamed, and cut with more precision. The Rice is also stress relieved, twice I believe, and the bore finished with a carbide plug to insure better uniformity and smoothness. Colrains are six groove, Getz and Rice are seven, which could be a factor in PRB accuracy, but I am not sure it would mean any practical difference. As I see it, geometricly, in a given caliber, with equal depth of round bottom groove, placeing seven grooves in the space that six might occupy, would give a sharper angle at the edge of the land, and the extra groove would also offer that much more to grip the PRB. This can however, be over done, as in the case of the first TC's that hit the market with, as I recall, twelve grooves. Their accuracy was pretty bad, and within a year TC went to less grooves. On the other hand, I may be as full of it as a Christmas turkey, but I will say, I have experienced enough bad luck with Colrains, that I will not buy any more, nor recommend them. It would seem that many suffer from noticeable loose, and tight spots, and roughly reamed bores. I have had to lap two of them, after all else failed, just to be able to put all shots somewhere in the black at fifty yards, I did however, use one in a gun a few years back that is a one hole group tack driver, but I would have to regard it as an exception, and not the norm.