Yes, you may load conical bullets upside down.
However, you'll need to reduce the powder charge somewhat, to make room for the bullet being longer when seated.
Accuracy probably won't be much to brag about. I've loaded conicals backwards, hoping to get a quasi-wadcutter, but accuracy was worse than the regular conical.
The most accurate projectile remains a ball, in my experience, though the Lee conical bullet has proven accurate in my Uberti-made Remington .44 Army. The Lee bullet has a smaller diameter body at the base, so it slip-fits into the chamber and helps to straighten the ball before ramming.
But for consistent accuracy, use a ball of .454 or .457 inch. The oft-recommended ball of .451 inch has never been as accurate as the larger diameter balls in any of my cap and ball sixguns.
At what distance are you shooting? 25 yards?
Are you shooting offhand or from a benchrest with a solid pistol rest?
If you're shooting offhand, your "low and left" problem may be simply how you're holding the revolver; or you may have a flinch.
If, however, you've decided that the sights are at fault then you may wish to adjust them a bit.
If the front sight is dovetailed into the barrel, tap it very slightly to the left to bring the group to the right. Yes, that's right: the front sight goes the opposite direction of where you want the bullets to hit.
As for it shooting low, this indicates that the front sight is too high. This can be remedied by
very lightly filing down the front sight.
But before you file the sight find an accurate load and adjust your sights to that one, accurate load.
Finding an accurate load begins with good components:
A. Black powder, in FFFG grade. Black powder substitutes are not as accurate.
B. Well-formed, round ball of .454 or .457 inch. "Round ball" is admittedly a redundancy but in this case it refers to the need to have well-formed balls. I favor Speer over Hornady; I've almost always found a few Hornady balls out-of-round in each box.
C. A well-greased
felt wad between the ball and powder. I stress real felt, made of wool. Much of today's felt is polyester (plastic) and leaves melted plastic in the bore, affecting accuracy.
D. Use natural greases or oils, both for loading and for rust preventative in the bore. Olive oil works well as a rust-fighter after you've cleaned the bore.
The best lubricant I've found is the one named after me: Gatofeo No. 1 Lubricant. It's composed of canning paraffin, mutton tallow and real beeswax. A wool felt wad soaked in Gatofeo No. 1 lubricant outperforms wads soaked in other natural greases or oils.
Natural greases and oils include lard, vegetable oil, bacon grease, Crisco, Bore Butter, CVA Grease Patch (my personal favorite for commercial lubes), coconut oil and so on.
Petroleum-based greases and oils, when combined with black powder, leave a hard, tarry fouling that affects accuracy.
E. Use caps that fit properly. The cap should bottom out, with its priming compound resting on top of the nipple's cone. A cap too small won't bottom out and cause misfires. A cap too large will fall off, or worse, allow a jet of flame into an unfired chamber and you'll get multiple chambers going off.
I don't believe that multiple ignitions begin at the front of the cylinder. I believe they start at the rear, when flame enters through a nipple.
I don't believe that placing grease over the ball prevents multiple ignitions because I can't see how flame can get past a properly sized ball, rammed in the chamber and clinging tightly to the chamber walls.
Well, these are my opinions, based upon more than 35 years of shooting cap and ball sixguns and trying just about every propellant, cap, projectile(s), grease, oil and lubricant out there -- including spit
Some folks will tell you, "Gatofeo's so old, he used to grease his Colt Navy with brontosaurus drippings."
They're lying.
It was mastadon grease ... and it was an 1836 Paterson.
