Hi Bill, I posted on your other post too.
I dont know much about this, but am mighty interested in Bore rifles that throw big blue whistlers
With rifled choke tubes, I have heard that there is a danger of the threads blowing out as the bullet slams into the rifling...also the prob of regulation....I just haven't seen much positive feed back when the rifled tube has been tossed out to chew on, thats all.
Most seem to go with sleeving a double with rifled tubes & regulating it like a regular rifle.
Like I said over at the other section..A nice single would be fun (Cheaper) & alot easier to regulate...just get the sights onto the hole your making in the target,lol.
If by chance the two holes are close before regulation, I believe I have heard of people putting a sight on each bbl.
Keep us posted Bill.
I have a modern NEF/H&R 20 bore single rifled slug gun, which I cast Balls for...it very accurate, but woefully ugly
cheers mate
Franc