I have found with the H barrel (as i got an unissued and unfired one; still in the grease) the bedding style that I have come across in trial and error, plus also discussing it with Lithgowicon and the armoury sector, is having the knoxs form touching and the nose cap also touching (around 4-6 pound of pressure on the barrel) with nothing else being in the way.
nose cap is also not drilled out.

manages to shoots 3"-4" groups at 200 yards, with 150 grain .310 projectiles all day, from both a cold barrel to a hot barrel with no issue, and no float with barrel warming up, so im pretty happy with it.
but like all SMLE shooters will agree with, is; find what works for your barrel, what works with one doesnt always mean it will work with all of them.