SLAMFIRE1
Remember the original 1873-1886 Springfields were set to zero at 250 yds. If you want to zero closer you need to raise the front sight.
Google says the blade is pinned into the base and can be replaced with a taller one made out of flat stock. Look closely.
How in the world did you get a full 70gr of FFg Black Powder into a 45-70 case when topped with a modern 405gr internally lubed bullet? (especially when using FFg) I thought the older black powder rifle cartridges and the 45 Colt never did fit the original powder charge in the case once we moved away from using a healed bullet.My original 1873 Trapdoor, mfg. in 1878, shoots Penn Bullets 500gr RNPB on top of 70gr compressed 2F about 3" high at 100yards. At least it groups about 4 MOA, given my inexperience with rifles I consider that pretty good. Too bad is also shoot 6" to the right!
I haven't tried to group the 405gr FPPB yet, I expect they would impact a little higher as the velocity would increase.
These are fun guns to shoot with Black Powder and will get attention at the range.