breech seating bore diameter pp

[bruce moulds]

so how did breech seating start in the creedmoor game?
who knows, but here is a guess.
the 45 2 7/8 case was tried with 100 gns of powder and found to be not bad. this in 1876.
we often read of the americans quoting 100 gns as the ideal charge for 1000 yd shooting, while the poms felt that 90 gns was enough. there could have been differences in powder.
by the end of 1876 the 2.6 case was introduced as being superior for target shooting with the same load, only the bullet more exposed to the rifling.
still using the same load, in 1877 the 2.4 case was introduced. again exposing more bullet at the same cartridge overall length.
it is hard to say how much 100 gns of powder filled the old 2.4 cases, but pictures of loaded rounds show the bullet way out. in fact they look longer than 2 7/8 hunting ammo.
these bullets were almost being breech seated when the cartridge was chambered.
it would only be natural for someone sooner or later to go the full monte.
or maybe people were starting to breech seat, and the shorter cases were an attempt to retain a marketplace for loaded ammo.
from reading hinman we know that at the end of the era people were breech seating using the 2.6 case full with more than 100 gns of powder.
a perfectly normal human action. we all look for more speed and power, even today.
keep safe,
bruce.