That is true, but I use it on wood that either is already naturally colored [walnut...] or has been stained [aqua fortis, etc.]. It seems to dry in a reasonable time, but perhaps not as fast as a production maker of guns would like 
...as an artist [of sorts] I have used artists linseed oil for over 50 years--it has worked for me whether on canvas or on wood...
I understand completely and you are on the right track except for color of the oil (IMO anyway).
But the point I am trying to make is the dark oil improves the wood stained or not.
Walnut especially responds very well to dark oil. Any natural oil is good but a dark oil acts like a subtle stain that darkens areas that absorb more oil. It also makes the right color fill on walnut.
While "stand" oil type products have been available for centuries they were not used by gunstockers due to cost. It took a long time to make the oil for artists use. A gallon or more of stock finish can be made in a couple of hours and then used as soon as cool.
It gives better color and definition to the wood and was cheaper to make.
Once of the reasons for lifeless modern stocks is the finish used. Clear plastic finishes often used are especially bad and leave a finish and color that makes the wood nearly one dimensional like the grain was painted on.
I know people who used Varathane because "linseed is not water proof". One can tell a stock finished with this stuff at a distance.
The shiny coating applied to many modern guns, I am thinking of a Browning SS I had to refinish when the plastic delaminated from the wood when I installed a plate in the wrist for a tang sight.
It was a nice piece of Walnut but nearly lifeless. I had to use epoxy stripper to get it off and refinished (for free) with oil. The difference was striking.
It is likely that a similar result would have been obtained with stand oil or similar but IMO the dark oil does a better job.
We all do things that we find work best for us. I certainly would not try to say your approach is wrong. On the contrary IMO it is fundamentally right for a stock finish. I just like the dark oil
This whole thing is an ongoing exercise for me. I am thinking about linseed oil varnishes now.
The dark remnants found on original rifles intrigue me. The finish on Vincent Ohio rifles needs more looking at. Building a Vincent without this finish tends to leave the project lacking.
The reddish/reddish brown/brown (now at least) varnish seen below appears on a great many rifles, some in the "museum" here show it.
This rifle is a S. Hawken once owned by Jim Bridger. The finish is well worn but is full to near full depth on the buttstock and in other low wear areas. It has NO checks, cracks or flakes or ANY failure aside from being worn away. It is obviously a boiled oil varnish with pigments/driers that give it color and allowed it to dry to a shine of greater or lesser brightness. It is surely the only color put on the wood. This stuff, used well into the cartridge era in various colors some much like stand oil in color but usually fairly dark, was often put on without a brush according to some who have looked closely at some varnished 1870s-80s BL guns. Rubbed on apparently showing the pattern of the finishers skin in the finish under magnification. But???
The varnish on the Hawken is (now) dark brown but closer examination show a lot of red undertones. making me wonder what the original color was and if it was really all that "bright" when new, its fairly dull now. Bright shiny finishes were not recommended for use on the plains since they acted like signal mirrors and could be seen to the horizon, or at least many miles if they reflected the sun to the distant person.
But I digress
Dan
