breech seating bore diameter pp

[bruce moulds]

a contentious issue, but here goes.
previous thinking was that creedmoor was shot with fixed ammo, but recent reading of maj hinman suggested that at least at the end of the era breech seating was the norm. a recently posted photo of a famous shooter's reloading gear included a breech seater, which reinforces hinman.
local scheutzen shooters have been on at me to try breech seating for some time, so I had to go cap in hand to them seeking advice.
they recommended trying the bullet 1/16" to 1/8" in front of the case, and that best accuracy would come once the bullet base was in front of the leade angle.
my rifle has a 7 degree per side combined transition/leade angle, meaning that pure barrel diameter starts about 1/10" in front of the case.
experiments started at 1/16", which returned accuracy similar to the fixed ammo control.
at 1/10", the rifle came alive with a pronounced improvement in group size, and at 1/8" I could not believe how well shooting was happening. no point in going further.
I am not worried about ringing the barrel with this airspace using bore diameter pp bullets, as compressed air cannot be retained until the bullet bumps up, as well as the fact that none of the local scheutzen guys have ringed a barrel with small airgaps. time might prove me wrong, and if it does, it will be part of learning.
case was droptubed full of powder with a 0.060 wad level with the top of the neck. the odg used a "pasteboard" wad for this.
confetti was absolutely perfect, unlike fixed ammo where the bases were blown off, probably as the bullet cleared the transition.
this seems to be part of the reason for improved accuracy. total avoidance of the transition offers one less chance for inconsistency.
now it is necessary to shoot this ammo at all ranges from 300 to 1000 to see how it holds up, and if it does, go on out to 1200. this will probably take a year, a job requiring patience.
this ammo requires wiping, which can be dealt with in sil, but the added loading time would make things tough in this discipline.
long range paper shooting on the other hand could benefit from breech seating if vert is diminished significantly.
with bore diameter pp bullets, seating requires little force, eliminating the need to use a leverage device.
keep safe,
bruce