I can so remember that BLO was considered "the" finish used by the old timers. So of course, every gun I refinished, I just had to use BLO. I tried it every which way. I tried it with Japan added and some days it would feel like it firmed up. Then someday you would have the gun in a rack outdoors in the sun and it would feel like you touched the finish with "Off" on your hands. After many years of thinking I was doing something wrong, I just gave up and stripped all the guns that I still owned that had BLO on them and I am glad I did. IMHO, there is no way that a builder of the period, could and would have taken the time, to build and sell a gun with that finish. It really never does dry and it holds dirt as well. The builder of a gun would have way to many hours in his build to make money at building and selling guns. As an original finish, it is hard to say with certainty, but after having pretty a fair number of original guns from the late 1700's and newer, pass through my hands. I find it extremely hard to believe that this very soft finish was ever used by the original builders. I can see where BLO maybe part of the recipe to make a fine finish, but it in my honest opinion, was never a finish that was a stand alone finish. In time, by itself, it will make the wood pithy and weak. This is my experience based on the years I have used it or seen guns that it had been used on. I next went to Tung Oil. It gives a nice finish, but it isn't as hard as I would like to see a finish. It also doesn't seem to be as weather resistant as it should be. It is though easy to touch up. The last number of years, I have used Tru-Oil. Yes, you can make Tru-Oil look any way you want, from a very high sheen to a very flat finish and everything in between. Touch up is easy and great as well. It has become my "go to" finish and it does seem to match the texture and finish that was used on the original guns, very well. I am sure there are other finishes that are very good as well, but almost anything, IMHO, is better than BLO.
About 15yrs. ago, I had refinished my 1979 Lyman GPR with BLO. About 6 yrs. ago, stripped off the gummy substance and I used Tru-Oil. What a relief it was and now the gun doesn't feel like a clammy handshake when you pick it up. :wink: