I cannot comment on Buffalo Arms ammo specifically, but the main reason the Army went to the .45-55-405 cartridge for the carbines instead of the .45-70-405 was the fact that the average cavalry trooper was about 5' 4" and weighed about 135 lbs, and there were concerns about recoil. Given, early on, the troops were allowed only three rounds per man per month (later increased to maybe 5 rds), and marksmanship wasn't emphasized until after Little Big Horn, the carbine load was deemed less punishing. However, some troop commanders requested full-power rifle loads for their troopers' carbines. Since you are probably a bit bigger (most of us are nowadays), and may not really notice the difference, strength-wise there is no reason not to shoot infantry loads in the carbine, presuming the carbine is safe to shoot at all.