I have been using Glass Coat as a finish on my wood grips and inserts and wanted to try Tru-Oil. I understand the concept of multiple coats and sanding with OOOO steel wool between coats. My problem is that when sanding, the dried Tru-Oil picks up the fibers from the steel wool and gives the wood a gray tint (from the fibers). What is the trick to properly use this product on wood grip and prevent this problem? Thanks!

You aren't waiting long enough for it to dry if you are using steel wool. If the previous coat is trapping the steel, it's too soon.

Use fine grit paper instead. 1000 to 2000 grit. Steel wool is great if you have a lot of time, but if you are talking terms of a couple of days... go with paper.

The trick for me is not to use steel wool. I hate the stuff for the reason you mentioned and the fact that it is almost impossible to clean it off between coats if the work has joints and edges for it to settle into. Plus it has oil in it.

I be sure I have raised the grain of the wood several times before finishing and have gotten rid of all the fibers that will pop up and grab stuff. Then I sand between coats with sandpaper. 400 or 600 wet or dry or 220 al oxide. Light touch, 1 finger pressure, small piece of sandpaper. Don't ride the edges.