I suspect Keith will try for 2,150fps to 2,200fps with the 220's in his Canadian P-14 Mauser. In a modern falling block, specifically a Ruger #1, I don't see any trouble adding 100fps to those. It all depends on the brass, how well it is fit to the chamber before being fireformed and when things get sticky. Due to the very tapered case, sticky comes long before modern-type high pressures will be reached. In either action, you'd be able to load to slightly sticky extraction, then back off a good 2gr. with a Hodgdon Extreme powder - 3gr. for others. I suspect the Ruger would allow slightly higher speeds at maximum loads.
: Improving the case to an Ackley or Epps deign would result in .308 Winchester ballistics - slightly better than standard.
: The original 215gr. Dominion(Imperial) bullets were wonderful on our moose. The Woodleighs would be as good or better, but are not available here.