The rifling (if unmodified) is very shallow and that is by design.
There is no method to "realign" the sights as they are military from the period again, if unmodified. Also, expect the gun to shoot high compared to our modern expectations. That was also by design from the period.
We shoot these guns in competition in the North South Skirmish Association here in the US. I just returned from our National competition last weekend. There's no other competition in the world like ours that balances speed and accuracy and is shot as a team against other teams.
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The "fog of war" frequently pays our National range a visit. Note this is position 64 of 70 and each position will hold an 8 man team and each position is occupied during an event (part of a match). Each match has 5 events and there are usually 3 Relays. A Relay is the next group of teams shooting the same event. Yeah, we burn a lot of black powder and there are more than a couple "Zouaves" out on the line. My son shot one on our team last weekend and he hammered his share of targets.
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