Gussy,
Back in the '70's, there was a place in Phoenix where you could build your own guitar, Juan Roberto School of Luthiery. John Roberts used Watco Danish Oils for finishing all his guitars, using a similar technique of many sessions of rubbing in the oil with 400+ wet/dry black paper, and after a few sessions, used just a shiny paper he had a huge roll of to rub the oil deep into all the pores. It really did make a difference in the sonic qualities of the instruments from what I could tell.
I refinished an old Marlin bolt action with the Watco's and it still has a beautiful luster that I so appreciate. I may just do the same with my 550 now that I see your results, though it has a nice factory finish. I just think the oil finish is more durable and looks better than sprayed on coatings.
Nice work, and thanks for sharing. Nicest looking 10/22 I've seen, great stock!