Opening smoothbore barrel

[JiriK]

I have a .45 smoothbore flintlock pistol.
It´s barrel is a bit odd, first inch or so is tight. Then bore opens up a bit and closes again close to the powder chamber (maybe last 1/2").

Uniform diameter for the entire length of the barrel would be optimal. How to get that? Adjustable reamer? Lead pin + lapping compound? Other methods?

 

[Scorch]

45 smoothbore flintlock pisto

Buck and ball gun?

first inch or so is tight

Yes, that's called a "choke", it helps the shot travel more accurately.

Then bore opens up a bit and closes again close to the powder chamber (maybe last 1/2")

Again, not unusual. Many breech plugs have a cone-shaped recess in them.

 

[JiriK]

Patch + round ball. I use .457 ball and 0.3mm patch.

This gun is used in MLAIC event Cominazzo.

 

[Scorch]

Well, if it is not intended to shoot shot, then the barrel will need to be reamed until the bore is true. Or replace the barrel. Unless you need it to be a smooth bore, a rifled pistol will be more accurate. And yes, harder to load, too.

 

[JiriK]

It has to be smoothbore according to event rules.

 

[mehavey]

Before we start removing metal.... Does it matter?

Is the accuracy with snug ball&patch reasonable at standard smoothbore pistol ranges?