Ihave seen some good " lucky " groups that did not hold up to scrutiny when put over a chronograph. They could not be repeated. When you have shot enough to understand good and bad days, and lucky shots, and shooting way above your average, you will understand better why I recommend using a chronograph. It does tell you much about inconsistencies in your loading and cleaning techniques, particularly if you use it in all for seasons, and on both rainy and sunny days, in all four seasons. You learn about powder performance in good and bad weather, what lubes work well in some weather, and not in others, and you learn what you have to do based on the temperature and humidity to keep the gun shooting, and hitting CLOSE to the POA.
None of this is particularly important if the longest shot you will take is at 50 yds, and at a deer sized target standing broadside to you. I would like to think that you don't really believe that a 470 grain bullet is needed to kill either a deer or elk with a ML rifle. At 437.5 grains to the ounce, your slug is way over any reasonable weight for hunting these sized animals. And being that heavy, it is no long range shooter, either, as it will be dropping like a rock after 120 yds.
I don't know what you have against chronographs, but I overcame my reluctance the first day I used mine, and learned far more information that I thought was possible. I eliminated a lot of unnecessary shooting, changed some habits about loading my rifle, change my practice in cleaning it, and have since learned some very interesting ideas about loading and firing ML guns from people on this forum that have proven out over the chronograph. It won't cook lunch, but its a valuable tool for working up loads.
Can a load be worked up that works well, and shoots well without a chronograph? Of course, it can. But you need luck, or lots of time to get there. I have experienced luck with a couple of guns and a couple of loads. I am always delighted at my " Luck ", and celebrate it just like the next guy does. However, I have also spent days and days trying to solve accuracy problems with my guns, and some have taken more than 30 years to figure out, only because it took that long to finally read some suggestions from other shooters that " fixed " the problems. I am still learning, and I have been reloading for about 50 years now, with one gun or another.
Now back to the issue. My experience, and the experience of other shooters who have shot musket caps instead of standard #11 caps is that the musket caps are much hotter, and that the produce wide variations( spikes) in velocity over using the standard caps. Accuracy does suffer. But the guys I am discussing these things with are slug gun, and chunk gun shooters, who test everything to perfection. They are shooting heavy slugs at long ranges, and they need every bit of edge they can get to shoot small groups at 500 and more yards. Any of their guns and loads would shoot rings around anything you may have and I know I have. A hotter cap is not always the better choice for accurate loads. In Black Powder cartridge shooting, Paul Matthews( the Dean of the .45-70, who is still experimenting and writing in his 80s) is finding out that standard pistol primers work best to ignite compacted loads of FFg powder in his .45-70s, rather than large rifle primers, and both are better than the Magnum Rifle primers, regardless of company of origin. Who would have thought that could be true, considering how much press such primers get in shooting large cartridges with smokeless powder loads???