Under - yeah - its a 1:28. I wouldn't want them any smaller. I think I may just head on down to the gun shop tomorrow and order a sizing kit in .451" and some 405 gr bullets.
I think with a little more playing with charges and maybe some felt wads, I can get them to shoot pretty good. If not, I can always fall back on the saboted .40 cal bullets. I'm not sure if those little pills would be reliable for deer. I'm pretty sure the 405 would have plenty of juice even for bigger game. Heck, there was enough bison that fell to this bullet.