The grain in a wood stock has both wide, summer growth "rings", and narrow, " Winter growth rings".
I get that effect, by putting a red stain on the stock that soaks into the wide grain. Then I sand off the stain from the harder, winter growth wood, around it. Now, with those Open pores still holding the "cherry Stain", I use a walnut stain( or some other for different woods, or different colors) on the stock. That also fills the larger pores of the summer growth, going on top of the red stain, and mixing with it a bit. If the red stain has been allowed to dry sufficiently, you will still see red in the grain after applying the walnut stain.
That two stain effect seems to make the grain POP when an oil finish is applied to the wood. I think that is what you are asking about. :thumbsup:
ALWAYS try new stains, and process out on similar scraps of wood. At the least, test these things out in the barrel MORTISE, where whatever color you get will be hidden by the barrel from view. Or use the end grain under your butt plate, for testing colors, and finishes. You should be sealing all exposed wood in a gun stock, one way or another. That includes: under inlays, mortises for the barrel, lock, trigger guard, patch box, the tang, and under the muzzle cap, the entry pipe, the ramrod hole in the stock, and under the butt plate, side plate, and toe plate.
I hope that helps. I am sure there are other ways to enhance grain colors, but this has worked for me on a number of stocks over many years. The last stock I tried this out on was a plain grain birch stock on a modern rifle. Its factory finish included brown PAINT, that I removed with acetone. I used cherry stain as described above, and followed with one coat of walnut stain( alcohol based). Then I finished the stock with hand rubbed coats of B/C Truoil.
The owner didn't recognize his gun when I returned it to him.I had to show him the serial number, and our note describing the serial number he gave to me with the gun, before I could convince him it was the same gun. That was fun to do. And his joy at getting an old, beat-up and neglected .22 rifle back looking better than new made it all worthwhile for me.