I have always heard that a heavier bullet will normally have a higher POI, at least in handguns. But I haven't experimented with it either.
Seriously! The proof is in the targets! If you like the rifle that is all that matters.No reason to be down in the jaws. Bannerman sold a lot of surplus rifles that were parts guns. They had a good reputation as far as selling functional rifles. In the day you couldn't get away with selling junk like they do now. They had no collector value but even that has changed. A Trapdoor is a collector's item in today's world even a Bannerman. If you have a good solid shooter you are ahead of the game.
I always loved my trapdoors. They are a ton of fun to shoot. I noticed that you're rear sight is of the M73 variety. If the sight is marked up to 1200 yards it is the carbine version. The rifle versions were only marked up to 1100 yards. (I know.. only). The M73 Rifle sight is calibrated for the 405 grain 45-70 pill at 1350 fps. If your rifle was indeed manufactured in 1878 and nobody bubba'd with the front sight, the 405 grain projectile is what the gun was tuned for. The carbine sight is calibrated for a 405 grain bullet at 1100 fps.Did some more digging--looks like a 405 gr bullet was the original loading but that gave way to a 500 gr bullet. I wonder if the POI/POA offset with the 405 gr bullet at close range was the reason behind the switch?
My rifle does indeed have the carbine rear sight with the C stamped onto it and the further range numbers milled off. It also has the later model ramrod so I think my Trapdoor could be a Bannerman parts rifle originally sold in the early 1900s. Or--it could be a Bubba job done in someones backyard over the years. It does shoot pretty decent---so I don't have any qualms that it isn't all original.I always loved my trapdoors. They are a ton of fun to shoot. I noticed that you're rear sight is of the M73 variety. If the sight is marked up to 1200 yards it is the carbine version. The rifle versions were only marked up to 1100 yards. (I know.. only). The M73 Rifle sight is calibrated for the 400 grain 45-70 pill at 1350 fps. If your rifle was indeed manufactured in 1878 and nobody bubba'd with the front sight, the 405 grain projectile is what the gun was tuned for. The carbine sight is calibrated for a 405 grain bullet at 1100 fps.
The 45-70-500 loading was tuned for the Model 1884 Trapdoor Rifle. Unbubba'd 1884 models can be identified by the year stamp on the breach block and will wear a buffington rear sight.
I've read Spencer Wolf's book quite a few times and if you really want to learn the ins and outs of the rifle I highly recommend that you get it. I think the website is 45-70book.com. If memory serves me, Spencer says that the Trapdoor is a reverse "jump" rifle. Reductions in powder weight below the original 70 grains normally results in the rifle printing higher. I'm not sure why this happens, but I've experienced it several times playing with mine.
I've had good luck with Accurate 5744 as it fills the cartridge case well, prevents double charges and isn't position sensitive.
If you really want to turn heads at the range, get yourself some Goex Fg or FFg black powder and stuff that under the 405 grain pill. Flame literally shoots 5 feet out the 32" barrel when you touch one off.
Good luck with the rifle and let me know if you have any questions.
When looking at the many pics from the Springfield Armory Trapdoor book, my rear sight is a standard carbine rear sight with the farther yard distance graduations ground off. Supposedly with the shorter barrel and slightly different loading, the Army Ordnance folks didn't think the carbine was capable of reaching out where the rifle model was "engineered to do". Someone put the wrong rear sight on my Trapdoor since its the longer rifle model. There are no Army Supply or Ordnance markings on my wood stock either which probably indicates that it is some type of after market replacement. Coupled with the wrong model ramrod---who knows what others parts were mixed and matched on the rifle. It could definitely be a Bannerman surplus patchwork quilt rifle or maybe one that some local put together out of spare parts. What really matters is that it shoots pretty decently for something possibly 150 years old.I'm not sure if you got a Bannerman rifle. The mix match of parts can be indicative of either a Bannerman Rifle or someone's bubba job. If the barrel is not a 3 groove barrel, can can be a sign of a Bannerman job. Some of their rifles sported 5 groove barrels.
The carbine rear sight with the range graduations ground off... that's got me. Normally you don't see that unless the front sight has been modified to be dead on at a desired range. Assuming that you're throwing them down range at 1350 FPS and 10 inches high at 50 yards... zero is somewhere around 220 yards. That's a weird place for bubba to set a zero.
What really matters is that it shoots pretty decently for something possibly 150 years old.