Baal
You are correct, BUT real actual BLO is linseed oil that was boiled in a sealed container until the raw linseed oil was polymerized and formed long interconnecting molecular chains (plasticizing the oil) which strengthened it and made the oil more water proof.
PROBLEM, the majority of modern made BLO today is raw linseed oil that has not been boiled and just has resins added to thicken it and chemical driers added to speed drying. If you put modern BLO in a heated tank it would start to harden as it turned into a thick linseed oil jelly and it would not penetrate “into” the wood.
During the war the Enfield stocks were dipped in a tank of hot linseed oil during manufacture which filled the wood cell structure, if the linseed oil is not reapplied the oil dries out and the wood begins to shrink.
The old linseed adage for applying linseed oil to a new stock, Once a day for a week, once a week for a month, once a month for a year and once a year for life.
Raw linseed oil will penetrate deeper into the wood rehydrating it and cause the wood to swell, and this swelling may be enough that shimming the stock will not be required. The problem is our Enfield stocks are as dry as a popcorn fart and need a good soaking in linseed oil. A wall paper wetting tray makes a good soaking tank and may prevent shortening the trigger guard bushing and shimming the fore stock.
Looking up the manufactures MSDS sheet for BLO will tell you if it is modern fake BLO or actual boiled linseed oil.
Below fake BLO with chemicals added that can make your genitalia fall off.
http://www.newparks.com/PDF/MSDS/SOLVENTS/BoiledLinseedOil.pdf
"Raw linseed oil is just that - linseed oil mercilessly squeezed from flax seed and packaged with no additional additives or preservatives. Raw linseed oil dries very slowly, taking weeks to fully cure. You should limit its use to the insides of wood gutters, chopping blocks, sawhorses, and other items exposed to the elements where drying time is not an important consideration.
Slow drying is a mixed blessing. For oil-based paints and varnishes, slow drying is a benefit, since this allows the paint to "level" itself, giving a smoother finish with fewer brush marks. The best looking paint jobs are invariably oil paint jobs, without question. However, when used as a wood preservative for items that are handled or walked on, such as tool handles, furniture, or wood decks, long drying times are undesirable. 100% Pure, this slow drying oil has multiple uses. It helps wood retain its natural moisture, aids in water repellency, retards cracking, checking and shrinking. Boiled linseed oil, though, is not boiled. The actual boiling of some varnish oils changes their drying characteristics. With linseed oil, though, it is the addition of certain solvents that causes linseed oil to dry more quickly, acting as if it were boiled. This makes it a better product for preserving tool handles, decks, and furniture. I suppose they should have named it "sort-of-boiled linseed oil", or "kinda-like-boiled-but-not-really-boiled linseed oil". Boiled Linseed Oil is used as a natural wood finish and preservative, either alone or with other oils and solvents. Mixed with oil based paints and varnishes, it increases gloss and improves leveling and durability. A mixture of 2 parts boiled linseed oil to one part turpentine creates a semi-gloss wood polish for furniture. Can also be mixed with mineral spirits."
Real raw linseed oil and actual boiled linseed oil can be found in craft stores that sell material for oil painting.
Below left to right, raw linseed oil, boiled linseed oil and boiled linseed oil with resins and odorless paint thinner added. NOTE, none of the linseed oils below contain any toxic chemicals and can be applied with your bare hands.